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About Unicode To Punycode Converter Online
This tool converts Unicode-containing domain names (like ☃.com or 例え.jp) to their Punycode (ASCII) representation that DNS can actually understand. The output uses the standard "xn--" prefix followed by the encoded label.
Punycode encoding is required to register or query internationalized (IDN) domain names. Browsers, DNS resolvers, and email servers all communicate using the Punycode form even though users see and type the Unicode form.
Use it when registering a domain that includes non-ASCII characters, when configuring DNS records for an IDN, or when copying a domain name into a system that only accepts ASCII.
How to use this tool
How to convert a Unicode (IDN) domain to Punycode
Paste the Unicode domain
Drop the internationalised domain into the "Unicode domain" field — e.g. `münchen.de`, `日本.jp`, `paypal.com` with a Cyrillic а. Trim spaces aren't required; they're stripped.
How encoding works
Internally the tool calls `punycode.toASCII()`, which applies the IDNA Nameprep + Punycode chain. Each label that contains a non-ASCII character is encoded with an `xn--` prefix; pure ASCII labels are passed through unchanged.
Press Run
Output is a single `punycode` field — the ASCII-compatible form ready for DNS. The result is what your browser sends in HTTP/TLS connections under the hood.
Use for DNS, TLS, and email
DNS resolvers, TLS certificate SANs, and SMTP envelopes need the Punycode form; visual displays can stay as Unicode. Save the Punycode version when configuring infrastructure to avoid encoding mismatches.