Punycode Converter
View an internationalized domain as the ASCII hostname produced by the browser’s URL parser. This checks its transport-oriented form, with an important limit on reverse conversion.
- Runs in your browser
- Nothing is uploaded
- No signup; device limits apply
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How to use this tool
Enter a domain or an HTTP/HTTPS address. Host extraction can remove the path and port; supplying an xn-- label does not cause this implementation to decode it back into Unicode.
Results and examples
Entering bücher.de can show xn--bcher-kva.de as the ASCII host. With only the ASCII form supplied, the Unicode-side field can remain unchanged rather than reconstructing the original characters.
Limitations
- There is no dedicated reverse xn-- decoder in the current implementation.
- Domain registration, trust and visually confusable names are not verified.
Fields
| Field | Guidance and constraints |
|---|---|
| Domain | Check the unit and format displayed beside this field. |
| ASCII / Punycode (hostname) | Check the unit and format displayed beside this field. |
| Unicode display | Check the unit and format displayed beside this field. |
Data handling
Processing stays in the current browser tab; the site does not upload tool input for the calculation itself.
Sources
Frequently asked questions
How is an internationalized domain displayed?
Entering bücher.de can show xn--bcher-kva.de as the ASCII host. With only the ASCII form supplied, the Unicode-side field can remain unchanged rather than reconstructing the original characters.
Does it restore Unicode from xn--?
There is no dedicated reverse xn-- decoder in the current implementation. Domain registration, trust and visually confusable names are not verified.
