Blackjack (21)
Your bet
Play money only — no real wagering. A natural blackjack pays 3 : 2, an ordinary win pays even money, and a push returns your stake; the house edge means the balance drifts down over time, just like the real game.
About Blackjack
Blackjack — also called 21 — is the most popular casino card game. You play one hand against the dealer, aiming to finish with a total closer to 21 than the dealer without going over. Number cards are worth their face value, face cards are worth 10, and an Ace is worth 11 or 1 — whichever helps most. Beat the dealer and you win; go over 21 and you bust and lose.
How to play
- Pick a stake and deal — you and the dealer each get two cards.
- One dealer card stays face down. If either two-card hand is a natural blackjack (an Ace with a ten-value card), the hand resolves right away.
- Otherwise take your turn: Hit to draw another card, Stand to keep your total, or Double to double your stake, take exactly one more card, and stand. Going over 21 busts and loses immediately.
- When you stand, the dealer reveals the hole card and draws until reaching at least 17 — the dealer stands on all 17s, including a soft 17.
- Whoever is closer to 21 wins. A natural blackjack pays 3 : 2, an ordinary win pays 1 : 1, and an equal total pushes (your stake is returned).
Card values and soft hands
- 2 through 10 — worth their face value.
- Jack, Queen, King — each worth 10.
- Ace — worth 11 unless that would push the hand over 21, in which case it counts as 1.
- A hand holding an Ace still counted as 11 is called soft (for example, Ace + 6 is a soft 17) — it cannot bust on the next card. Once the Ace must count as 1 the hand is hard.
Basic strategy at a glance
Basic strategy is the mathematically best play for every hand against the dealer’s upcard. A few durable rules of thumb:
- Always stand on a hard 17 or higher; always hit a hard 11 or lower.
- Stand on 12–16 when the dealer shows 2–6 (the dealer is likely to bust); hit 12–16 when the dealer shows 7 or higher.
- Double a hard 11, and usually a 10, against a weak dealer card.
- Never take insurance — it is a losing side bet over time.
This is a simplified summary; a full basic-strategy chart adjusts for soft hands and pairs.
How it works
- Each card is drawn by generating a cryptographically secure 32-bit unsigned integer in your browser
- The integer is mapped to one of the 52 cards using modular arithmetic — every rank and suit equally likely, reshuffled each hand
- Ace totals, natural blackjacks, and the dealer’s stand-on-17 play are all computed locally
- Your bet is settled and the balance updated — instantly, with no server request
Simplifications and follow-ups
This is a single-hand game against the dealer. Splitting pairs, insurance, surrender, multi-hand play, and a card-counting trainer are possible future additions — for now, focus on the core hit / stand / double loop and the 3 : 2 blackjack payout.