Punycode is an encoding scheme that converts Unicode characters into the ASCII-compatible format used by DNS.

Why do IDNs need Punycode?

The DNS system was designed for ASCII characters only.

The xn-- prefix signals a Punycode-encoded domain label.

IDN Punycode Converter

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Convert internationalized domain names (IDN) to Punycode (xn-- format) and back.

IDN → Punycode Punycode → IDN

Input Result

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Internationalized Domain Names allow domain names to contain non-ASCII characters. Punycode converts these to ASCII-compatible format.

What is Punycode?: Punycode is an encoding scheme that converts Unicode characters into the ASCII-compatible format used by DNS.
Why do IDNs need Punycode?: The DNS system was designed for ASCII characters only.
What does xn-- mean?: The xn-- prefix signals a Punycode-encoded domain label.

Last updated: 2026-05-24