Crypto

Punycode Encoder / Decoder

Convert IDN domains to ASCII (xn--) and back. Internationalized domain names. 100% free.

How to use

  1. Enter a domain, URL, or value relevant to Punycode Encoder / Decoder.
  2. Run the check and review the output carefully.
  3. Apply recommended fixes, then run the check again to verify.

Common use cases

  • Pre-deployment validation for Punycode Encoder / Decoder.
  • Incident triage when security checks fail in production.
  • Periodic security review as part of technical SEO and hardening.

Example inputs

münchen.dexn--mnchen-3ya.de日本語.jp

Common issues and fixes

Invalid punycode

Decode fails on malformed xn-- strings. Check format.

Mixed scripts

Some domains with mixed scripts may fail ACE encoding.

Recommended remediation

Punycode (RFC 3492) encodes Unicode to ASCII for DNS. Prefix xn-- indicates encoded label.

FAQ

Is Punycode Encoder / Decoder free to use?

Yes. This tool is free and can be used without account registration.

Do you store submitted values?

Only the minimum processing needed for the check. For client-side tools, data stays in your browser.

How should I use these results?

Use the output as a diagnostic baseline, apply fixes in your stack, then re-run the check to confirm remediation.

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