What is Punycode used for?

Punycode (RFC 3492) encodes internationalized domain names that contain non-ASCII characters into a limited ASCII form prefixed with xn--, so the existing DNS system can route them.

Does it convert whole domains?

Yes. Each dot-separated label is handled independently — Unicode labels gain the xn-- prefix when encoded, and xn-- labels are turned back into Unicode when decoded.

Is my domain sent anywhere?

No. The full Bootstring algorithm runs in your browser, so the domains you enter never leave your device.

Punycode Converter — Gera Tools

Punycode converter for internationalized domains

Punycode is the encoding from RFC 3492 that lets internationalized domain names (IDNs) work with the ASCII-only DNS. A label such as münchen becomes xn--mnchen-3ya, and the reverse turns it back. This tool implements the full Bootstring algorithm and processes a domain one label at a time, so münchen.de round-trips cleanly to xn--mnchen-3ya.de and back.

Pick encode or decode, enter your domain, and the converted form appears instantly — all locally in your browser.