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Encoding

Convert Unicode domain names to punycode

Punycode Converter maps Unicode domain names to the ASCII form that DNS actually resolves. The domain münchen.de, for example, is stored and looked up as xn--mnchen-3ya.de, where xn-- marks an encoded label. Registrars, whois records, and zone files all use this ASCII form, so anyone registering an internationalized domain with accented, Cyrillic, or emoji characters needs the conversion. Conversion runs label by label: labels made only of plain-ASCII characters pass through unchanged, while a non-ASCII label is encoded following the RFC 3492 rules every browser implements, so .de and other ASCII parts stay untouched.

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How to use Punycode Encode

  1. Open Punycode Encode in the Toolbox101 app.
  2. Type or paste the domain with non-ASCII characters, for example münchen.de.
  3. Read the Output box, which shows the ASCII form (such as xn--mnchen-3ya.de) as you type, with ASCII parts like .de unchanged.
  4. Click Copy to put the punycode domain on your clipboard and use it where ASCII-only names are required.

Worked example

Punycode Encode returns the output below for this input.

Input

münchen.de

Output

xn--mnchen-3ya.de

Check it yourself: open Punycode Encode and enter the same input.

Frequently asked questions

When does the converter leave a domain unchanged?

Labels made only of plain-ASCII characters pass through untouched: example.com returns as example.com. Only labels that contain characters outside the plain-ASCII range, such as ö, Cyrillic letters, or CJK characters, are converted to their xn-- form. The conversion is applied label by label, so a mixed domain like münchen.de becomes xn--mnchen-3ya.de with .de unchanged.

What does xn-- mean in a domain name?

xn-- is the prefix that tells DNS resolvers a domain label holds punycode. Everything after the prefix (literal ASCII letters plus a base-36 payload) encodes the original Unicode characters. münchen becomes xn--mnchen-3ya, where -- separates the kept letters from the encoded part.

Do I need a punycode converter to open Unicode domains?

Not for browsing. Browsers convert Unicode and xn-- forms automatically. You do need the conversion when a system only accepts ASCII: registering an IDN, querying whois, writing zone files, or pasting a domain into legacy tools that reject non-ASCII input.

Are emoji domains encoded as punycode too?

Yes. An emoji is a Unicode character like any other, so it encodes to punycode the same way: a pizza-emoji label encodes as vi8h, making the domain xn--vi8h.com. Because emoji render so differently from Latin letters, browsers deliberately show the xn-- form for such domains to prevent lookalike confusion.

Use Punycode Encode now

Open Punycode Encode in the app

Runs in your browser. Nothing you type is uploaded.