Rangdom

Rangdom updates

Changelog

Product notes for new generators, private browser tools, and small improvements that make Rangdom easier to use.

Generate sample ISINs by country, a whole batch at a time

The ISIN fixture generator used to hand you one code from a random country. Now you can pin it to the market you care about — pick US, GB, DE, FR, JP, CA, CH, AU, NL, or IT, or leave it on random — and ask for up to 50 valid codes at once instead of clicking through them one by one. Every value still carries a correct check digit and stays clearly synthetic, and you can copy the whole batch as plain lines, CSV, or a JSON array to drop straight into your test data, spreadsheet, or fixtures. When you have a real code to check, the validator is still one click away.

ISIN Fixture GeneratorISIN Validator

Check whether a UK NHS Number is valid

Got a 10-digit NHS Number and need to know if it's well-formed? A new validator checks its Modulus-11 check digit as you type, tells you plainly whether the number is valid, and shows the expected versus supplied check digit alongside the neatly grouped number. When the check digit is wrong it even suggests the corrected number, and it flags length or stray-character mistakes separately so you know exactly what's off. Spaces and hyphens are ignored, everything runs in your browser with nothing sent to a server, and it pairs directly with the random NHS Number generator for quickly producing and checking test data.

NHS Number ValidatorRandom NHS Number Generator

Look up any HTTP status code, then test yourself on it

Ever pause to remember whether a request should return 401 or 403, or what 422 actually means? A new HTTP status codes page lays out every code from 1xx to 5xx, grouped by class, each with its reason phrase and a plain-English note on when it applies. Type a number or a keyword to filter down to the codes you care about, then switch to the built-in flashcard quiz that shows a code, offers four reason phrases to pick from, scores each answer, and tracks your current and best streak. It's the reference-and-practice companion to the random status code generator, and it all runs right in your browser.

HTTP Status Codes Reference & QuizRandom HTTP Status Code Generator

Go straight from a generated ISIN or BIC to checking a real one

Generating a sample ISIN or BIC often comes with the flip side of the task: you also have a real code sitting in front of you that needs verifying. Both generators now link straight across to their validators, so you can confirm an ISIN's ISO 6166 check digit or a BIC's ISO 9362 structure without hunting for the right page. The ISIN generator goes a step further and points to the related CUSIP, SEDOL, and LEI validators too, making it a quicker hub for anyone working across securities identifiers.

ISIN GeneratorISIN ValidatorBIC / SWIFT Code GeneratorBIC ValidatorCUSIP ValidatorSEDOL ValidatorLEI Validator

Find your zodiac sign by birthday, then drill all twelve

Wondering which star sign a birthday falls under? A new zodiac page settles it: pick a month and day and it names the sign, glyph, date range, element, and ruling planet, getting the cusp dates right down to the day. Below the finder sits a full reference chart of all twelve signs from Aries to Pisces, and a flashcard quiz that flips up a glyph, offers four names to choose from, keeps score, and tracks your current and best streak. It's the study-and-practice companion to the random zodiac pick, and everything runs entirely in your browser.

Zodiac Signs Chart, Birthday Finder & QuizRandom Zodiac Sign

Grab a fake credit card number for testing

Looking for a test credit card number to run through a checkout form? The payment card generator now makes that plain. It hands you a fake, Luhn-valid card number with a recognizable brand prefix — Visa, Mastercard, American Express, or Discover — plus a matching expiry and CVV/CVC, so your validation logic and payment UI see a realistic-looking value without any real card ever being involved. Everything is synthetic fixture data, generated right in your browser and never usable for an actual transaction, and it's now far easier to find whether you search for a payment card, a test card, or a fake credit card number.

Fake Credit Card Number Generator

Study and drill the Tamil alphabet

Tamil joins the chart-and-quiz lineup, so you can learn the script and practice it on the same page. The alphabet page lays out all 31 base letters — the 12 vowels (uyireluttu) from A (அ) to Au (ஔ), the 18 consonants (meyyeluttu) from Ka (க) to Na (ன) in their standalone form, and the āytham (ஃ) — each with its name, glyph, and romanization, alongside a flashcard quiz that shows you a letter, offers four choices, keeps score, and tracks your current and best streak. Want a quick flip-through instead? The companion generator hands you one random Tamil letter at a time for recognition drills. As always, everything runs entirely in your browser with nothing sent anywhere.

Tamil Alphabet Chart & QuizRandom Tamil Letter

Jump straight to the number generator you actually wanted

Reaching for a random number and landed on the wrong one? Nine of the number generators now point you to their closest neighbors right on the page, so you can move in a single tap instead of heading back to search. The digit-length pages step you up and down the ladder — 2-digit to 3-digit, 4-digit to 6-digit — and over to the PIN code generator when that's really what you needed; the decimal, decimal-range, and normal-distribution tools link across to one another and to a custom range; and the small everyday ranges connect out to the 1–100 pick, dice, the lottery draw, and shuffling into a random order. It's a small thing that makes finding the right tool feel a lot less like a maze.

Random 2-Digit NumberRandom 6-Digit NumberRandom DecimalNormal DistributionRandom Number Set

Georgian, Armenian, and Bengali scripts — and a search that does the math

The chart-and-quiz format reaches three more of the world's writing systems, so you can study a script and drill it live on the same page: the 33 letters of Georgian's flowing Mkhedruli, the 38 letters of the Armenian alphabet in both upper and lower case, and the Bengali (Bangla) varnamala of vowels and consonants — which also gains a single-letter generator for quick flip-through practice. Each quiz shows you a letter, offers four choices, keeps score, and tracks your current and best streak, with the full reference chart right there to study from. Picking a plain number got faster too: type a range like "2-5" or just "20" into the homepage search and you now jump straight into a pre-filled generator instead of hitting a dead end. And for the everyday small ranges, there are one-tap pages ready to go — 1–3 for a three-way call, 1–4 as a d4, 1–5 for star ratings, 1–6 as a fair die, 1–7 for a day of the week, and 2–5 for ranges that start above one. As always, everything runs entirely in your browser with nothing sent anywhere.

Georgian Alphabet Chart & QuizArmenian Alphabet Chart & QuizBengali (Bangla) Alphabet Chart & QuizRandom Bengali (Bangla) LetterRandom Number 1–6Random Number 2–5

Learn five more scripts, from Kana to the Thai alphabet

The chart-and-quiz format now reaches five more of the world's writing systems, so studying a script and drilling it live happen on the same page. Japanese leads the way: the Kana page pairs a full 46-sound gojūon reference with a flashcard quiz and a Hiragana / Katakana / Both toggle, so you can practice either syllabary or shuffle the two together. Four more alphabets that until now had only a single-letter generator get the same treatment — the Devanagari varnamala behind Hindi, the 22-letter Hebrew aleph-bet, the 28-letter Arabic abjad, and all 44 Thai consonants. Each shows you a glyph, offers four choices, keeps score, and tracks your current and best streak, with the whole reference chart right there to study from. As always, everything runs entirely in your browser with nothing sent anywhere.

Hiragana & Katakana (Kana) Chart & QuizDevanagari (Hindi) Alphabet Chart & QuizHebrew Alphabet (Aleph-Bet) Chart & QuizArabic Alphabet (Abjad) Chart & QuizThai Alphabet Chart & Quiz

Alphabet quizzes that actually teach, and more scripts to read

The alphabet tools grow from generators into a way to learn. Three new chart-and-quiz pages pair a full reference table with an interactive flashcard drill: the Greek, Cyrillic (Russian), and Korean Hangul alphabets each show you a glyph, offer four choices, keep score, and track your current and best streak so you can practice until the letters stick — with the whole chart right there to study from. If you'd rather just flip through one letter at a time, the single-letter generators reach three more writing systems: the 28-letter Arabic abjad from Alif to Ya, the Devanagari varnamala behind Hindi and Sanskrit, and the 44 Thai consonants from Ko Kai to Ho Nokhuk, each shown with its name, glyph, and romanization. Together with the Korean Hangul generator, that's a broader tour of the world's scripts for anyone learning to read a new one. As always, everything runs entirely in your browser with nothing sent anywhere.

Greek Alphabet Chart & QuizCyrillic Alphabet Chart & QuizKorean Alphabet (Hangul) Chart & QuizRandom Arabic Letter GeneratorRandom Devanagari Letter GeneratorRandom Thai Letter GeneratorRandom Korean Hangul Generator

A full casino card table, plus Cyrillic and Hebrew letters

The games corner grows into a proper casino floor. Four classics arrive together, each playable against a fair, verifiably random deal and a play-money bankroll you can win and lose without spending a cent: Keno, where you mark 1–10 spots on an 80-number board and watch twenty numbers drop to see how many you catch; Baccarat (Punto Banco), which deals the Player and Banker hands to the exact third-card rules and lets you back either side or the tie; Blackjack (21), a full Hit / Stand / Double hand against a dealer who stands on all 17s, with 3:2 naturals; and Video Poker (Jacks or Better), where you hold the cards you like, draw the rest, and get paid off the standard 9/6 paytable. Every game shows its odds and payouts up front, so you can learn how each one really works before you ever sit at a real table. Away from the felt, language learners get two more alphabets to drill: a Random Cyrillic Letter generator covering all 33 letters of the modern Russian alphabet and a Random Hebrew Letter generator covering the 22 letters of the aleph-bet, each with its name, glyph, and transliteration. As always, everything runs entirely in your browser with nothing sent anywhere.

KenoBaccarat (Punto Banco)Blackjack (21)Video Poker (Jacks or Better)Random Cyrillic Letter GeneratorRandom Hebrew Letter Generator

A much bigger color toolbox, plus schedules, ciphers, and fixtures

The largest single push yet for the color toolbox, alongside a fresh crop of tools and fixtures. Six new color generators land together: a Tailwind CSS palette picker that hands you a utility token like blue-500 with its matching hex and swatch; a print-ready CMYK generator for packaging and brochure mockups; the intuitive HWB (hue–whiteness–blackness) and design-tool HSV/HSB models used by Figma, Photoshop, and Sketch; CSS Color 4's LCH, the natural companion to OKLCH; and a Color Scale generator that builds a full 50–950 tint-and-shade ramp from a random base hue, ready to paste as design-system tokens in a HEX list, CSS variables, or JSON. Beyond color, a Round-Robin Schedule generator turns a list of participants into a fixture list where everyone plays everyone — with byes for odd counts and an optional home-and-away double round — and a Nihilist Cipher joins the classical-cipher workbench, layering a running additive key over a keyword-built Polybius square. The encoding tools grow too: Base45 encode and decode (the alphanumeric format behind EU COVID-certificate QR codes), plus an MD5 option added to the Text Hash Generator. Rounding out the day are a checksum-valid UK NHS Number generator for healthcare fixtures, a CNPJ Validator that completes the Brazilian ID pair next to the CPF Validator, and two playful pickers — a Pet Name generator and a Random Fruit generator for classroom games and mock data. As always, everything runs entirely in your browser with nothing sent anywhere.

Tailwind Color GeneratorCMYK Color GeneratorHWB Color GeneratorHSV Color GeneratorLCH Color GeneratorColor Scale GeneratorRound-Robin Schedule GeneratorNihilist CipherBase45 Encoder/DecoderText Hash GeneratorNHS Number GeneratorCNPJ ValidatorPet Name GeneratorRandom Fruit Generator

Everyday calculators, a friendlier password, and Brazilian ID tooling

A full day of additions across the toolbox. Three practical calculators land: an Age Calculator that turns a birth date into exact years, months, and days, totals in weeks and months, the weekday you were born on, and a countdown to your next birthday; an Ohm's Law Calculator that takes any two of voltage, current, resistance, and power and solves for the rest; and a Daily Calorie Calculator that estimates your BMR and TDEE from the Mifflin–St Jeor equation across every activity level. The password lineup gains a Pronounceable Password option that strings together consonant–vowel syllables into something you can actually say and type — with a live entropy readout so the tradeoff stays honest. And for anyone building or testing software for Brazil, there's now a matched set: generators for synthetic CPF and CNPJ numbers with correct check digits, a CPF Validator to check and correct them, plus an ORCID iD generator for researcher-identifier fixtures. As always, everything runs entirely in your browser with nothing sent anywhere.

Age CalculatorOhm's Law CalculatorDaily Calorie CalculatorPronounceable PasswordCPF GeneratorCNPJ GeneratorCPF ValidatorORCID iD Generator

Four more ciphers, two game-night pickers, and a fuller toolbox

Another wide batch lands across the toolbox. The classical-cipher workbench grows by four: a keyword-based Simple Substitution cipher that scrambles the whole alphabet rather than just shifting it, the digit-keyed Gronsfeld variant of Vigenère, the self-reciprocal della Porta cipher that swaps the alphabet's two halves, and the World-War-I ADFGVX cipher, which fractionates letters and digits through a keyed 6×6 square before a keyword columnar transposition. Each shows the live square or alphabet it's working from, toggles between encode and decode, and is checked against textbook reference vectors. Game night gets two fair pickers: a Chess960 (Fischer Random) generator that draws any of the 960 legal starting back ranks with its Scharnagl position ID, and a Mahjong tile generator that deals a hand from the full 144-tile set with each tile's glyph, readable name, and category. Two format-correct fixtures join the mock-data set — clearly-fictional AWS resource IDs for EC2, EBS, VPC, and more, and UK National Insurance Numbers that follow every HMRC prefix and suffix rule while always starting with a never-issued letter so they can't collide with a real person. Rounding things out, a Margin & Markup Calculator turns a cost and a sale price into profit, gross margin, and markup side by side — settling the two figures sellers most often confuse — and a JWT Encoder signs real, verifiable HS256/384/512 tokens that check out against the JWT Decoder and jwt.io. As always, everything runs entirely in your browser with nothing sent anywhere.

Simple Substitution CipherGronsfeld CipherPorta CipherADFGVX CipherChess960 Position GeneratorMahjong Tile GeneratorAWS Resource ID GeneratorUK NINO GeneratorMargin & Markup CalculatorJWT Encoder

Six more classical ciphers, plus seed-phrase and SIN fixtures

The cipher workbench gets a serious upgrade for anyone working a puzzle, CTF challenge, or cryptography lesson. On the keyword side, the Beaufort cipher joins Vigenère with its self-reciprocal twist — the same operation both encodes and decodes — and the Autokey cipher extends the keystream with the plaintext itself so the key never repeats, defeating the repeating-key analysis that cracks plain Vigenère. The square-and-grid family fills out too: the Bifid and Trifid ciphers fractionate each letter into coordinates on a 5×5 Polybius square or a 3×3×3 cube and regroup them across a configurable period, while the Two-Square (double Playfair) and Four-Square ciphers encrypt letter pairs through two or four keyed squares — the missing rungs between single-square Playfair and the rest of the digraph ciphers. Each shows the live square or cube it's working from, toggles between encode and decode, and was checked against the textbook reference vectors. Two new fixture generators round things out: a BIP39 mnemonic generator that produces checksum-valid 12-to-24-word seed phrases against the official English wordlist for testing wallet and backup flows, and a Canadian SIN generator that builds Luhn-valid, correctly-shaped numbers with a never-issued leading zero so they can't collide with a real person's. Everything runs entirely in your browser.

Beaufort CipherAutokey CipherBifid CipherTrifid CipherTwo-Square CipherFour-Square CipherBIP39 Mnemonic GeneratorSIN Generator

Read what's inside your IDs, plus more text and tabletop tools

If you've ever stared at an opaque identifier and wondered when it was created, three new decoders now read it for you: paste a TypeID, a Firebase Realtime Database push ID, or a MongoDB ObjectId and see its embedded creation timestamp (in UTC and your local time) plus the fields packed inside — a TypeID's prefix and the UUID it wraps, or an ObjectId's machine and counter bytes. For text and ciphers, a Letter Frequency Analyzer counts every letter in a passage and charts them from most to least common, the natural first move when breaking a substitution cipher, while a Punycode / IDN converter turns internationalized domains like münchen.de to and from their xn-- form so you can see what a host really resolves to. A JSON Flatten / Unflatten converter collapses nested JSON into dot-and-bracket path keys and rebuilds it again, handy for diffing, i18n files, and config. Tabletop players get a dice pool roller that counts successes against a target number for systems like Shadowrun and World of Darkness, and a new IMSI fixture generator rounds out the telecom mock-data set with synthetic subscriber identities that can never collide with a real network. Everything runs entirely in your browser.

TypeID DecoderFirebase Push ID DecoderMongoDB ObjectId DecoderLetter Frequency AnalyzerPunycode / IDN ConverterJSON Flatten / UnflattenDice Pool RollerIMSI Fixture Generator

Auth fixtures, more encoders, and a wider reference shelf

This update stretches the toolbox in every direction. Building or testing two-factor flows is easier now: generate a Base32 TOTP shared secret with its matching otpauth:// provisioning URI, or a correctly-shaped bcrypt password hash to seed a users table — both clearly fictional fixtures that never touch a real account. Three additions join the encoding shelf, each handling text in both directions: Ascii85 (the dense format used in PDF and PostScript), MIME Quoted-Printable (the transfer encoding email uses), and a Unicode escape converter that turns text to and from \uXXXX, \u{…}, and \xXX so you can make any string ASCII-safe or read one back. Scaffolding types from a sample payload is quicker too — paste JSON and get Go structs or Python dataclass/Pydantic models, with json tags, optional-field handling, and sensible number inference. A new pattern-string generator fills a custom mask like ???-#### for license keys, invoice codes, and mock IDs. And the for-fun and reference shelf grows with random blood type, musical note, compass direction, Scrabble-style letter-tile rack, Chinese zodiac, and planet pickers — handy for fixtures, flashcards, classroom prompts, and game nights. As always, everything runs entirely in your browser.

TOTP Secret KeyBcrypt HashAscii85 EncodeQuoted-Printable EncodeUnicode Escape ConverterJSON to GoJSON to PythonPattern StringRandom Blood TypeRandom Musical NoteRandom Compass DirectionLetter TileRandom Chinese ZodiacRandom Planet

Oracles, more ID formats, and a wider toolbox

This update widens almost every shelf at once. Two new oracle draws join the for-fun generators — cast one of the 64 I Ching hexagrams in traditional King Wen order, or draw a single Elder Futhark rune with its glyph, sound, and meaning. For mock data and fixtures there's now a CUID2 generator for Prisma-style IDs, a denser Base85 (Z85) string generator, and a fake database connection string builder that produces obviously-fictional but correctly-shaped PostgreSQL, MySQL, MongoDB, and Redis DSNs for your .env examples and docker-compose files. UUID coverage gains name-based v3, the MD5 counterpart to v5, so identical inputs always produce the same identifier. On the conversion side, paste a JSON array of objects and get clean SQL INSERT statements with an editable table name and either one multi-row insert or a statement per row. The Polybius square cipher rounds out the classical-cipher collection with a 5×5 coordinate encode and decode, and a new CSS backdrop-filter generator hands you a ready-to-paste frosted-glass declaration with a live glassmorphism preview. Finally, if you work in healthcare, the NPI validator checks a 10-digit National Provider Identifier's check digit and shows the corrected value. As always, every one of these runs entirely in your browser.

Random I Ching HexagramRandom RuneCUID2Base85 StringDatabase Connection StringUUID v3 GeneratorJSON to SQLPolybius Square CipherCSS Backdrop FilterNPI Validator

A workbench for classical ciphers

The Caesar cipher had been on its own; now it anchors a whole shelf of classical ciphers you can encode and decode in one place. Scramble text with a repeating keyword in the Vigenère cipher, mirror the alphabet with Atbash, weave letters across a zig-zag in the Rail Fence cipher, hide each letter behind a five-symbol A/B group with Bacon's cipher, swap letters for their alphabet positions with A1Z26, rotate punctuation and digits alongside letters with ROT47, or combine a multiply-and-shift step in the Affine cipher — the generalization that has Caesar and Atbash as special cases. Each one is a single page with a direction toggle, live output, and a copy button, and is a natural fit for puzzles, CTF challenges, escape rooms, and intro-cryptography lessons. Three more tools round out the day: a prime factorization calculator that breaks a number into its primes in exponent and expanded form, a CRC32 checksum for verifying text the way ZIP and PNG files do, and random Geohash and Plus Code generators for working with location codes. As always, every one of these runs entirely in your browser with nothing sent anywhere.

Vigenère CipherAtbash CipherRail Fence CipherBacon's CipherA1Z26 CipherROT47 CipherAffine CipherPrime Factorization CalculatorCRC32 ChecksumRandom Geohash GeneratorRandom Plus Code Generator

Check the codes behind finance, publishing, and software

Rangdom could already generate identifiers like ISINs and ISSNs; now it can check the ones you already have. A new family of validators lets you paste a code and see at a glance whether it holds up: securities identifiers (ISIN, CUSIP, and SEDOL), the global Legal Entity Identifier (LEI), bank BIC/SWIFT codes, journal ISSNs, and software version strings checked against the full Semantic Versioning 2.0.0 spec. Each one does more than pass or fail — it shows the expected check digit and the corrected code when yours is off, breaks the value into its parts (a BIC's bank, country, and branch; a version's major, minor, patch, prerelease, and build metadata), and gives a specific reason when something is wrong instead of a blunt “invalid.” The generators grew alongside them, too: a CSS conic-gradient builder for pie charts, color wheels, and sweep backgrounds; a randomly seeded single-elimination tournament bracket that handles byes for you; Docker-style container names; compact Base36 short IDs; and sortable, time-ordered UUID v6 identifiers. As with everything on Rangdom, all of it runs entirely in your browser.

ISIN ValidatorCUSIP ValidatorSEDOL ValidatorLEI ValidatorBIC / SWIFT Code ValidatorISSN ValidatorSemVer Validator & ParserCSS Conic GradientTournament Bracket GeneratorContainer Name GeneratorBase36 StringUUID v6 Generator

Read any number in scientific notation

Rangdom already converts integers between radixes and spells numbers out in words, but nothing handled the way scientists, engineers, and developers actually write very large and very small values. The new Scientific Notation Converter fills that gap. Type a plain decimal like 0.00042 or E-notation like 6.022e23 and it shows four forms at once: the fully expanded standard form (602200000000000000000000), normalized scientific notation with a superscript power (4.2 × 10⁻⁴), engineering notation with the exponent locked to a multiple of three (420 × 10⁻⁶), and the copyable machine E-notation (4.2e-4). A significant-figures selector from 1 to 15 controls the precision of the scientific and engineering mantissas, while standard form and E-notation stay exact. It handles zero, negatives, and the full IEEE-754 double range, updates live as you type with a per-row copy button, shows a clear inline error instead of NaN for invalid input, and — like everything on Rangdom — runs entirely in your browser.

Scientific Notation Converter

A shelf of everyday calculators

Rangdom began as a place for random values, and it has quietly grown a practical second half: a set of calculators for the small math that comes up all the time. You can now split a restaurant bill and see the per-person tip and total, add tax to a price or back it out of a tax-inclusive total, take a percentage off to find a sale price, check a Body Mass Index against the standard weight bands, and estimate a loan or mortgage's monthly payment along with the interest it adds up to. There's a date calculator that adds or subtracts years, months, weeks, and days to land on a due date and its weekday; a statistics tool that turns a pasted column of numbers into the mean, median, mode, range, and standard deviation at once; and a quick greatest-common-divisor and least-common-multiple finder for exact integer math. Each one updates live as you type, shows a clear inline message instead of NaN when something doesn't add up, and — like everything on Rangdom — runs entirely in your browser with nothing sent anywhere.

Tip CalculatorSales Tax / VAT CalculatorDiscount / Sale Price CalculatorBMI CalculatorLoan CalculatorDate Add / Subtract CalculatorStatistics CalculatorGCD & LCM Calculator

What will my savings grow to?

The Loan Calculator works out what you owe on amortized debt and the Percentage Calculator handles everyday ratios, but neither answers the other half of personal finance: what will money grow to if it compounds? The new Compound Interest Calculator fills that gap. Enter an initial principal, an annual interest rate, a term in years, and a compounding frequency — annually, semi-annually, quarterly, monthly, or daily — and it shows the final balance, the total you contributed, and the total interest earned, updating live as you type. Add an optional regular contribution deposited at the end of each compounding period and it models a savings plan or recurring deposit as an ordinary annuity: the future value is P × (1 + i)^N + PMT × ((1 + i)^N − 1) ÷ i, falling back to P + PMT × N when the rate is zero. Amounts are shown to two decimal places as bare numbers, with an inline error instead of a result when input is empty, non-numeric, or negative, or when both the principal and the contribution are zero. It is the simple compounding formula only — no inflation, tax, separate contribution frequency, per-period breakdown, or continuous compounding — and like everything on Rangdom it runs entirely in your browser.

Compound Interest Calculator

How long is it from one time of day to another?

The Date Difference Calculator answers how far apart two calendar dates are, and the Duration Converter changes one duration between units — but neither answers the everyday question of how long it is from one clock time to another. The new Time Duration Calculator fills that gap. Enter a start and end time as 24-hour HH:MM or HH:MM:SS and it shows the elapsed time as H:MM:SS along with total hours (to two decimal places), total minutes, and total seconds, updating live as you type. When the end time is the same as or earlier than the start it wraps to the next day and labels the result as crossing midnight — so a 22:00–06:00 shift reads as 8 hours — the standard shift-length behavior for work shifts, study blocks, cooking timers, and meeting lengths. Empty, malformed, or out-of-range input shows an inline error instead of a result, and like everything on Rangdom it runs entirely in your browser.

Time Duration Calculator

Validate the identifiers you already have, not just generate them

Rangdom has always generated identifiers — now it can check them too. A new family of validators verifies the check digit on a number you paste in and tells you instantly whether it holds up: the Luhn Validator covers payment cards, IMEI, and any mod-10 number; the ISBN Validator handles both ISBN-10 and ISBN-13; the IBAN Validator confirms the country, length, and ISO 13616 checksum; the GTIN / Barcode Validator recognizes EAN-8, UPC-A, EAN-13, and GTIN-14; the VIN Validator checks a 17-character vehicle number; and the ABA Routing Number Validator covers US bank routing numbers. Each one detects the format for you, gives a clear valid-or-not verdict with the expected check digit, and offers the corrected value when something is off — and instead of silently passing bad input, it explains exactly what's wrong. It's the fast way to debug a number that won't validate, sanity-check imported data, or confirm a fixture before you ship it, and like everything on Rangdom it runs entirely in your browser.

Luhn ValidatorISBN ValidatorIBAN ValidatorGTIN / Barcode ValidatorVIN ValidatorABA Routing Number Validator

An NPI healthcare provider identifier fixture generator

The compliance-fixture family — SSN, EIN, and passport — gains an NPI Generator. The NPI is the standard 10-digit ID on US healthcare onboarding, credentialing, claims, and EHR/EDI forms, and it carries a Luhn check digit, so hand-typed fakes get rejected by validators. This generator produces synthetic, clearly-fictional NPIs: a base that starts with 1 or 2 (the only issued ranges) plus a valid Luhn check digit computed over the standard 80840 issuer prefix. Validators accept the shape while the values stay obviously fake, never a real provider — handy for form testing, seed data, screenshots, and demos. It runs locally in your browser.

Random NPI Generator

A SEDOL securities identifier fixture generator

The securities-fixture family — ISIN, CUSIP, and LEI — gains a SEDOL Fixture Generator. SEDOL is the primary identifier for UK and Irish listed instruments, and this generator produces synthetic, clearly-fictional codes in the modern 7-character form: a random 6-character base over the digit-and-consonant alphabet plus a valid weighted modulus-10 check digit. Parsers and validators accept the shape while the values stay obviously fake, never a real security — handy for seed data, form-validation tests, and mock brokerage, portfolio, market-data, and fund-admin payloads. It runs locally in your browser.

Random SEDOL Fixture Generator

Config converters, two developer calculators, and a wave of fixtures

This batch fills out the corners you hit while building and testing. Two converters tackle config files: the .env ↔ JSON Converter round-trips dotenv files and flat JSON in both directions — handling quoting, comments, and the export prefix — and the JSON to TOML Converter turns a JSON object into a clean TOML document with dotted table headers and arrays of tables. Two calculators answer questions you'd otherwise reach for a REPL to settle: the Bitwise Calculator computes AND, OR, XOR, NOT, and shifts on two integers with each result shown in decimal, hex, binary, and octal across 8- to 64-bit widths, and the Aspect Ratio Calculator resizes a width-and-height pair while preserving its ratio and shows the simplified form like 16:9. For mock data and seed fixtures, there's a new family of clearly-fictional generators: MD5 hashes and SSH key fingerprints for checksums and known_hosts mockups; ASIN, GTIN-14, and SSCC-18 codes — with valid check digits — for marketplace and logistics testing; Firebase Push IDs and GitHub-style identicon avatars for IDs and placeholder profile pictures; and a custom-range decimal generator that draws a random number between any min and max at the precision you choose. Rounding it out, a Roulette wheel spins European or American pockets with running red/black/green tallies. Everything runs locally in your browser.

.env ↔ JSON ConverterJSON to TOML ConverterBitwise CalculatorAspect Ratio CalculatorRandom MD5 Hash GeneratorSSH Key Fingerprint GeneratorRandom ASIN GeneratorGTIN-14 Barcode GeneratorSSCC-18 GeneratorFirebase Push ID GeneratorIdenticon Avatar GeneratorRandom Decimal Range GeneratorRoulette Spin Generator

Sharper data tooling, two new converters, and fairer draws

This batch sharpens the tools you reach for when wrangling data and settling a pick. For structured data, the XML Formatter & Validator pretty-prints, minifies, and checks XML — preserving attributes, comments, and CDATA — while JSON Diff compares two documents by structure rather than line order, calling out exactly which keys were added, removed, or changed, and JSON to JSON Schema infers a ready-to-use Draft-07 schema from a single sample payload. The Query String Builder assembles a properly URL-encoded query string from editable key-value rows, the inverse of the existing parser, and the Fraction ↔ Decimal Converter goes both ways between fractions, mixed numbers, and decimals. For drawing names and prizes, the Weighted Random Picker gives each option a weight and draws winners in proportion — ideal for loot tables and raffles — and the Secret Santa generator matches everyone to exactly one recipient so no one ever draws themselves. Rounding things out, a Passport Number generator produces clearly fictional, correctly shaped fixtures for test forms and seed data. Everything runs locally in your browser.

XML Formatter & ValidatorJSON DiffJSON to JSON Schema ConverterQuery String BuilderFraction ↔ Decimal ConverterWeighted Random PickerSecret Santa GeneratorRandom Passport Number Generator

Everyday calculators, more data-format converters, and keyed hashing

A fresh batch of tools landed for quick answers and data wrangling. Two everyday calculators settle the math you keep reaching for: the Percentage Calculator solves all three common questions — what is P% of N, what percent one number is of another, and the change from one value to the next, labeled as an increase or decrease — while the Date Difference Calculator tells you exactly how far apart two dates are, in total days, a years-months-days breakdown, weeks, and weekdays only. On the data side, the JSON family keeps growing: scaffold TypeScript interfaces straight from a sample payload, round-trip between JSON and XML in either direction, and flip between JSON Lines (NDJSON) and a JSON array. Compare Two Lists finds what's shared and what's unique between two pasted lists by set membership rather than line order, with a case-insensitive option. For developers working with tokens and signatures, there's an HMAC Generator for keyed SHA digests in hex or Base64, a pair of URL-safe Base64URL encode and decode tools for JWTs and OAuth parameters, and a classic time-based UUID v1 generator. Everything runs locally in your browser.

Percentage CalculatorDate Difference CalculatorJSON to TypeScript ConverterJSON to XML ConverterXML to JSON ConverterJSON Lines ConverterCompare Two ListsHMAC GeneratorBase64URL EncodeBase64URL DecodeUUID v1 Generator

A bigger converter family and new tools for developers

The unit converter family grew a lot this week. You can now convert power (watts, horsepower, BTU/h), frequency (Hz through THz, plus rpm), force, torque, acceleration, and density, each laying one value out across every common unit at once. A few converters tackle the units people actually fumble: the Data Transfer Rate converter handles the 8× bit-versus-byte gap so a 300 Mbit/s plan reads back as 37.5 MB/s; the Fuel Economy converter reconciles L/100 km against mpg and km/L even though one gets better as it goes down and the others as they go up; and the Running Pace converter turns a 5:00 min/km pace into min/mile, km/h, and mph. Developers get three new utilities too: a chmod calculator that keeps octal, symbolic, and a permission grid in sync; an IPv4 subnet calculator that breaks an address and prefix into its network, broadcast, mask, and host range; and a Unicode character inspector that reveals every code point — including the invisible and zero-width characters that quietly break diffs and parsers. As always, everything runs locally in your browser.

Power ConverterFrequency ConverterForce ConverterTorque ConverterAcceleration ConverterDensity ConverterData Transfer Rate ConverterFuel Economy ConverterRunning Pace Converterchmod CalculatorIPv4 Subnet CalculatorUnicode Character Inspector

Three new converters, six fresh fixtures, and a tarot draw

A big batch of tools landed today. Three more side-by-side unit converters join the set: turn one angle into degrees, radians, gradians, turns, arcminutes, and arcseconds; convert energy across joules, calories, kilocalories, watt-hours, kWh, BTU, and foot-pounds; and read a pressure value in pascals, kPa, bar, psi, atm, and mmHg at once. For test data, you can now mint synthetic but correctly-shaped fixtures — Luhn-valid ICCID SIM numbers, carrier-styled UPS/FedEx/USPS/DHL tracking numbers, SHA-256 digests (with the sha256: Docker/OCI form), W3C traceparent headers for tracing demos, a batch of 2FA backup codes in unambiguous lowercase, and an age-bounded date of birth that shows the computed age for KYC and form testing. Rounding things out: draw one card from the full 78-card tarot deck (with optional reversals), pull a random element from the periodic table, and roll a full set of D&D ability scores with the 4d6-drop-lowest method. As always, every value is generated locally in your browser.

Angle ConverterEnergy ConverterPressure ConverterICCIDTracking NumberSHA-256 HashtraceparentBackup CodesDate of BirthTarot CardChemical ElementAbility Scores

New generators for play, naming, and test data

A fresh batch of single-purpose generators landed today. Draw a random zodiac sign with its glyph, element, and date range, pull a Greek letter when you need a name for a math or physics variable, or spin up a kid-friendly animal for classroom games, charades, and Pictionary. For test data, the US identity set gains fictional Employer Identification Numbers in the NN-NNNNNNN format, and the book-identifier family adds legacy ISBN-10 values complete with a correct mod-11 check digit (the trailing X included). And for game night, a one-click 75-ball bingo card lays out a full B-I-N-G-O grid with a free center space that you can copy as a grid, CSV, or JSON. Every value is generated locally in your browser.

Zodiac SignGreek LetterRandom AnimalEINISBN-10Bingo Card

Invoice number generator

Rangdom's commerce/billing fixture set now includes invoice numbers alongside SKUs, coupon codes, currency amounts, and IBANs. Generate a fictional, human-readable invoice number such as INV-2024-481037 in the INV-YYYY-NNNNNN format — handy for billing screens, invoice PDFs, accounting seed data, and CRM/checkout demos. The value is generated locally in your browser with the Web Crypto API and is not a real or unique invoice number.

Invoice Number

ISO 8601 date-time generator

Rangdom's date/time family now emits full ISO 8601 instants alongside /date, /time, and /timestamp. Generate a random UTC date-time such as 2026-03-14T09:21:47Z within a configurable date range, toggling between seconds and millisecond precision — handy for createdAt/updatedAt columns, audit records, log lines, and JSON fixtures. Every value ends with a trailing Z and is generated locally in your browser with the Web Crypto API.

ISO 8601 Date-Time

Snowflake ID generator

Rangdom's sortable-ID family now includes Snowflake IDs alongside UUID v7, ULID, and KSUID. Generate one or a batch of up to 50 Twitter/Discord-style 64-bit identifiers as time-sortable decimal strings, packing a 41-bit millisecond timestamp with machine and sequence bits from the Web Crypto API — handy for seed data, API mocks, and database rows. Everything runs locally in your browser.

Snowflake ID

Caesar cipher and ROT13

Rangdom's text toolkit now includes the classic Caesar cipher alongside the Morse translator. Shift letters by any amount from 0 to 25 (with a one-click ROT13 preset) to encode and decode in either direction on a single page. Case is preserved, digits and punctuation pass through untouched, and everything runs locally in your browser — handy for puzzles, CTF challenges, and lightly hiding spoilers.

Caesar Cipher

Binary (Base2) encode and decode

Rangdom's encode/decode family now covers binary alongside Base64, Base32, and Hex. Convert text to a space-separated 8-bit Base2 byte string and back, with UTF-8 safe handling for emoji and non-Latin characters. Decoding is lenient: it accepts both spaced and continuous bit strings, all locally in your browser.

Binary EncodeBinary Decode

Hex (Base16) encode and decode

Rangdom's encode/decode family now covers hexadecimal alongside Base64 and Base32. Convert text to a continuous lowercase Base16 byte string and back, with UTF-8 safe handling for emoji and non-Latin characters. Decoding is lenient: it tolerates whitespace and an optional leading 0x, all locally in your browser.

Hex EncodeHex Decode

OKLCH color generator

Rangdom's color suite now emits OKLCH, the modern, perceptually-uniform CSS color model shipping in every major browser. Generate a ready-to-paste oklch() value with a live swatch and copy button for prototyping themes, picking accent colors, or seeding design tokens, all locally in your browser.

OKLCH Color

More local tools, fixtures, and privacy guidance

Rangdom now handles more day-to-day builder workflows in the browser: reverse text, turn headings into URL-safe slugs, generate regex-friendly sample strings, and create copyable fixture data as JSON Lines, XML, YAML, Markdown tables, or documentation-safe DNS records. The List Shuffler can copy results as lines, CSV, or a JSON array, the letter generator can pick from uppercase, lowercase, or either case, and new guides plus About, Contact, Privacy, and Terms pages make the site's local-first approach easier to understand.

Text ReverserSlugify TextRegex Test StringJSON LinesXML DataYAML DataMarkdown TableDNS RecordList ShufflerRandom LetterGuidesPrivacy Policy

More ready-to-copy fixtures and safer picks

Rangdom now gives builders more copyable data formats and clearer confidence checks in the browser: generate Base32 and binary strings, valid JSON objects or arrays, CSV rows, and accessible foreground/background color pairs, then copy them straight into docs, prototypes, seed files, or mock APIs. The name generator can create small batches, password tools now show live entropy estimates, timestamps can be copied as Unix seconds, ISO datetimes, or both, and the dice set now includes a dedicated D4 roller alongside a new CSS text-shadow helper for typography mockups.

Base32 StringBinary StringJSON ObjectJSON ArrayCSV DataColor PairRandom NameSecure PasswordUnix TimestampD4 Dice RollerCSS Text Shadow

More local tools for builders

Rangdom now covers more everyday development and QA tasks without sending your inputs anywhere: sort or dedupe pasted lines, parse query strings into decoded rows and JSON, generate safe query strings, ObjectId-style values, license plate fixtures, UTC offsets, private IPv4 addresses, and IPv4 or IPv6 CIDR blocks. The CSS toolbox also grew with copyable aspect-ratio, grid, flexbox, easing, and animation declarations for quick layout and motion prototypes, while dice notation now accepts shorthand like d20+5.

Text SorterDuplicate Line RemoverQuery String ParserQuery StringObjectIdLicense PlateUTC OffsetIP AddressCIDR BlockCSS Aspect RatioCSS GridCSS FlexboxCSS EasingCSS AnimationDice Notation

More local identifiers, fixtures, and CSS tools

Rangdom now helps with more of the setup work around demos, APIs, UI prototypes, and test data: generate sortable UUID v7 values, one or many Nano ID-style identifiers, complete fictional user profiles, product names, SKUs, job titles, locale tags, and HH:MM:SS durations. The token, batch UUID, and Nano ID tools can copy batches as lines, CSV, or JSON arrays, while new local CSS helpers generate ready-to-copy shadows, border radii, transforms, transitions, clamp-based font sizes, and filters; there is also a browser-only JWT decoder for inspecting token header and payload JSON without sending it anywhere.

UUID v7Nano IDRandom TokenBatch UUIDsJWT DecoderUser ProfileProduct NameSKUJob TitleLocaleDurationCSS Box ShadowCSS Border RadiusCSS ClampCSS TransformCSS FilterCSS Transition

More developer fixtures and format tools

Rangdom now covers more of the data you need when building, documenting, and testing products: generate sortable ULIDs, ISBN-13 fixtures, Unix timestamps, cron expressions, safe HTTP headers, documentation-safe domains and CIDR blocks, fixed-width PIN codes, fictional company names, and fake payment card fixtures. The color tools are more practical too, with copyable CSS gradients and palette exports for HEX lists, CSS variables, or JSON, while the new HTML entities tool helps encode or decode pasted text locally in your browser.

ULIDISBN-13Unix TimestampCron ExpressionHTTP HeaderDomain NameCIDR BlockPIN CodeCompanyPayment CardCSS GradientColor PaletteHTML Entities

Better fixtures and local text tools

Rangdom now makes it easier to fill realistic demos, forms, APIs, logs, uploads, and test data without leaving your browser. You can generate safe URLs, filenames, file sizes, MIME types, HTTP methods, ports, user agents, time zones, currency amounts, semantic versions, booleans, and documentation-safe IP addresses, plus count words or create SHA hashes locally when working with pasted text.

Random URLFilenameFile SizeMIME TypeHTTP MethodPort NumberUser AgentTime ZoneCurrency AmountSemantic VersionBooleanIP AddressWord CounterText Hash Generator

More mock data, color, and text tools

Rangdom now covers more everyday placeholder and testing needs: generate fictional names, addresses, ZIP-style codes, countries, US states, HTTP status codes, emoji, weekdays, months, and lorem ipsum text directly in your browser. The color tools are more useful for design work too, with RGB and HSL options in the color code generator plus a new five-color palette generator, while the time generator now supports custom ranges and the new case converter helps reshape text without leaving the page.

Random NameRandom AddressZIP CodeCountryUS StateHTTP StatusEmojiLorem IpsumColor CodeColor PaletteRandom TimeCase Converter

More flexible generators and URL tools

Rangdom now has more ways to generate values in the exact format you need: create one or many URL-safe tokens, roll custom dice or tabletop notation like 2d6+3, choose decimal precision, set hexadecimal string length, switch between IPv4 and IPv6 addresses, and make lowercase URL slugs for routes or mock content. New URL encode and decode tools also make it easier to prepare text for query strings and inspect encoded URL components without sending anything away from your browser.

Random TokenCustom DiceDice NotationRandom DecimalRandom HexIP AddressURL SlugURL EncodeURL Decode

New generators and smoother results

Rangdom now includes dedicated generators for single letters and fictional email addresses, plus date ranges you can set before generating a random date. Copy actions give clearer success or failure feedback, and more result areas now announce updates politely for screen reader users, making quick picks, rolls, passwords, UUIDs, usernames, and list tools easier to use without watching the page.

Random LetterEmail AddressRandom DateList PickerList ShufflerCoin Flip

Plan games, teams, and small decisions in one place

Rangdom now covers more of the little coordination tasks that come up during games, classrooms, meetups, and testing work. You can split people into fair teams or groups, pick a random pair, draw a card, settle a yes-or-no decision, and generate fictional phone numbers for examples without leaving the browser.

Team GeneratorGroup SplitterRandom PairRandom CardYes or NoPhone Number