Web

Punycode Encoder/Decoder

Convert internationalized domain names (IDN) between Unicode and ASCII-compatible Punycode encoding per RFC 3492

Unicode Domain / Text

Punycode Result

Was this tool helpful?

What is Punycode Converter?

Encode and decode internationalized domain names (IDN) between Unicode and Punycode using a pure TypeScript implementation of RFC 3492.

Convert domains with non-ASCII characters like umlauts, Chinese, Japanese, Korean, Arabic, Cyrillic, and emoji into their xn-- ASCII-compatible encoding. Supports full domain names with automatic label splitting, batch mode for multiple domains, and a Unicode codepoint inspector. Domain validation checks length limits and format rules. All processing runs locally in your browser.

How to Use Punycode Converter

1Enter a Unicode domain name or Punycode-encoded domain in the input field
2Select the conversion direction or let the tool auto-detect
3View the converted output instantly with domain validation info
4Use batch mode for converting multiple domains at once

Frequently Asked Questions

Punycode is an encoding system defined in RFC 3492 that represents Unicode characters using only ASCII characters. It is used to encode internationalized domain names (IDN) so they can work with the DNS system, which only supports ASCII.

The xn-- prefix (called ACE prefix) indicates that a domain label is Punycode-encoded. For example, 'munchen.de' with an umlaut becomes 'xn--mnchen-3ya.de'. The prefix tells DNS resolvers to decode the label.

Yes. Emoji characters are Unicode and can be converted to Punycode. However, most domain registrars do not allow emoji domain registrations due to security concerns around visual spoofing.

Yes. All conversion happens locally in your browser. No domain names are sent to any server.

Paste the xn-- domain into the decoder and it shows the readable Unicode name. This reveals IDN homograph attacks, where a phishing link uses lookalike characters from another script so that, for example, xn--pple-43d.com renders as apple.com. Decoding shows the actual characters before you click.

Yes. Switch to batch mode and paste a list of domains, one per line. Each line is encoded or decoded independently so you can process a whole set of URLs in a single pass.

Share this tool

Related Tools

B64

Base64 Encoder/Decoder

Base64 encode and decode online - convert text to Base64 or decode Base64 strings instantly, free

Text to Binary

Free online text to binary - convert text to binary representation and binary back to text

Tailwind to CSS

Free online tailwind to CSS - convert Tailwind CSS classes to vanilla CSS properties

···

Morse Code Converter

Free online morse code converter - convert text to Morse code and Morse code back to text with audio playback

🔄

ROT13 / Caesar Cipher

ROT13 encoder/decoder and Caesar cipher with brute force cracker and frequency analysis

Cron Expression Parser

Free online cron expression parser - parse cron expressions and see the next scheduled run times