Punycode Converter
Convert IDN domains to and from xn-- Punycode.
How to use
- 1 Choose a direction: Unicode to ASCII, or ASCII back to Unicode.
- 2 Type or paste the domain name into the input box.
- 3 Read the converted form in the output panel.
- 4 Copy the result to use in your registrar, code or address bar.
About Punycode Converter
The Punycode Converter translates between human-readable internationalised domain names and the ASCII form that the Domain Name System actually understands.
DNS was built for a limited set of ASCII characters, so a domain containing accents, umlauts, Cyrillic, Greek, Arabic or emoji must be encoded before it can be registered or resolved.
That encoding is Punycode, defined in RFC 3492, and each non-ASCII label is given the now-familiar "xn--" prefix — so "münchen.de" becomes "xn--mnchen-3ya.de".
This tool runs the full RFC 3492 bootstring algorithm directly in your browser, label by label, so you can encode a Unicode domain to its ASCII representation or decode an "xn--" address back into the readable original.
It is useful for registering IDNs, debugging email and TLS certificates that store the ASCII form, and for spotting homograph or phishing domains that disguise themselves with look-alike Unicode characters.
Because the conversion is entirely client-side, nothing you type is ever sent to a server, logged or stored — handy when you are inspecting a suspicious link.
Pure-ASCII labels pass through untouched, multi-label domains are handled in one pass, and the converter keeps working offline once the page has loaded.
FAQ
What does the "xn--" prefix mean?
It is the ACE (ASCII Compatible Encoding) marker that tells DNS resolvers a label is Punycode-encoded Unicode. Only labels with non-ASCII characters receive it.
Why are Punycode domains a security concern?
Different Unicode characters can look identical to ASCII ones, letting attackers register look-alike "homograph" domains. Decoding to Unicode and inspecting the xn-- form helps reveal such spoofing.