Punycode / IDN Converter

xn--mnchen-3ya.de
Converted locally in your browser. Encoding lowercases each non-ASCII label and rewrites it as an xn-- Punycode label (RFC 3492); decoding expands xn-- labels back to Unicode. Pure-ASCII labels pass through unchanged.

Encode a domain to Punycode

Turn an internationalized domain name like münchen.de into the ASCII-compatible form (xn--mnchen-3ya.de) that DNS, TLS certificates, and email headers actually carry on the wire. Each dot-separated label is handled on its own: pure-ASCII labels are left as-is, while labels with non-ASCII characters are lowercased and Punycode-encoded with an xn-- prefix.

When to use this tool

Reach for the Punycode converter when you need to see what an internationalized domain like münchen.de actually resolves to on the wire (xn--mnchen-3ya.de), or to decode an opaque xn-- host pulled from logs, TLS certificates, phishing reports, or email headers back into readable text. Encode rewrites each non-ASCII label as an ASCII-compatible xn-- label per RFC 3492; decode reverses it, expanding xn-- labels and leaving plain-ASCII labels untouched.

Privacy and limitations

Everything runs locally in your browser; nothing is sent anywhere and no DNS lookups are performed. This tool implements plain Punycode with per-label xn-- handling and lowercasing — it does not apply the full UTS-46 / IDNA2008 mapping, normalization, bidi, or registrability rules, so it is a wire-format converter rather than a complete IDNA validator.