Punycode Encoder/Decoder
Free online Punycode encoder and decoder. Convert internationalized domain names (IDN) to ASCII and back instantly.
What is Punycode?
Punycode is an encoding syntax that converts Unicode characters into ASCII, used specifically for internationalized domain names (IDN). For example, münchen.de becomes xn--mnchen-3ya.de.
Why is Punycode needed?
The Domain Name System (DNS) only supports ASCII characters. Punycode allows non-ASCII characters (like Chinese, Arabic, Cyrillic) to be used in domain names by encoding them as ASCII.
What is an IDN?
An Internationalized Domain Name (IDN) is a domain name that contains characters from non-ASCII scripts. IDNs use Punycode encoding to be compatible with the DNS system.
Is Punycode encoding reversible?
Yes, Punycode encoding is fully reversible. You can decode any Punycode string back to its original Unicode representation without any data loss.
How does this Punycode encoder work?
Simply paste or type your domain name or Unicode text into the input field. The tool instantly converts it to Punycode format (for encoding) or back to Unicode (for decoding). No registration or installation required.
What is the xn-- prefix?
The xn-- prefix is a special marker that indicates a domain name has been encoded using Punycode. It tells the DNS system that the following characters are in Punycode format and need to be decoded.
Can I encode email addresses with this tool?
Yes, you can encode the domain part of email addresses. For example, user@münchen.de becomes user@xn--mnchen-3ya.de. The local part (before @) should remain in ASCII format.
Is this tool free to use?
Yes, this Punycode encoder and decoder is completely free. No registration, no usage limits, and no hidden fees. You can convert as many domain names as you need.
What is RFC 3492?
RFC 3492 is the technical specification that defines the Punycode encoding algorithm. It was published by the IETF in 2003 as part of the IDNA (Internationalized Domain Names in Applications) standard.
Does Punycode work with all Unicode characters?
Yes, Punycode can encode any Unicode character, including Chinese, Japanese, Korean, Arabic, Cyrillic, Hebrew, Thai, and many other scripts. The encoding is lossless and reversible.
How to Use Punycode Encoder/Decoder
Convert internationalized domain names between Unicode and Punycode ASCII right in your browser. Nothing you paste is uploaded, so even production domains stay private.
- Type a Unicode domain such as the sample münchen.de into the Input field.
- Press Encode to transform it into the browser-facing ASCII form that starts with xn--.
- Paste an xn-- address into Input and press Decode to recover the readable Unicode domain.
- Turn on Auto convert to see the translation update live while you type, with no button press needed.
Convert only the hostname: email addresses and full URLs contain characters Punycode does not handle, so strip paths, ports, and schemes first.
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