Punycode Conversion
Convert a string to Punycode, or convert Punycode back
Features
Automatic direction detection
Automatically switch to encoding for Japanese and restoring for xn-- based on the content
Convert while keeping the URL structure
Keep the scheme, port, and path parts and convert only the domain
Batch convert up to 100 lines
Process multiple domains or URLs together, separated by line breaks
Try instantly with samples
Load examples of Japanese domains or xn-- format with one click
How to Use
Enter what to convert
Enter Japanese domains, Punycode, or URLs in the input field, one per line
Check the conversion result
The automatically detected converted string is shown on the right
Copy or save the result
Get the conversion result with the copy button or download button

Use Cases
Checking Japanese domain notation
Find out in advance which xn-- format an IDN is actually registered as
Safety check of URLs in email
Convert an unfamiliar xn-- domain back to Japanese to identify what it really is
Creating server configuration values
Accurately obtain the Punycode notation to register in DNS or certificates
Investigating internationalized domains
Restore the domain of an overseas site to readable characters to grasp its content
Basic Knowledge
What is Punycode?
Punycode is a method for converting internationalized domain names such as Japanese into ASCII strings beginning with "xn--". For example, "日本語.jp" is represented as "xn--wgv71a119e.jp".
Why is conversion necessary?
The DNS system that manages domain names can only handle ASCII characters and hyphens, so Japanese domain names cannot be registered as-is. Browsers convert Punycode internally, which enables Japanese URLs to work.
Safety and Privacy
Runs entirely in your browser
Your input data is processed only within your browser and is never sent externally.
Processing only in your browser
the two-way Punycode conversion is processed entirely within your browser, and input data is not sent to any server.
Communications encrypted with HTTPS
Page loading is also encrypted by TLS, and content cannot be read by third parties.
No transmission to third parties
Input content is not sent to external services such as ad networks or trackers.
No automatic saving of results
the domains you entered and the conversion results and input suggestions are not stored on the server.
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RAKKOTOOLS is free to use!
Available free of charge for individuals and corporations, commercial and non-commercial use alike.No prior permission or usage application is required. Feel free to use it in various situations.

Use in streaming and videos
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Use in schools, work, and events
Can be used in various situations such as classes, team division, internal work, and events.

Introduction on Web, books, and SNS
Feel free to introduce it as a useful tool on web media, books, SNS, and other platforms.

Commercial use
Can be used for commercial purposes such as research, calculation, processing, and conversion in business and production.
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If using in streaming and videos
Link to RAKKOTOOLS in the description, or Mention or display that you are using RAKKOTOOLS in the stream or video.
Credit example for the description
Usage guidelinesYou are free to use it for normal purposes. However, use for purposes that violate laws, infringe on third-party rights, impose significant load on the service, or otherwise interfere with service operation is prohibited.
We do not guarantee the accuracy or completeness of information and calculation results obtained from each tool.
This notice is a translation of the original Japanese text. If there is any discrepancy between the translation and the original, the Japanese original takes precedence.
