Punycode is a simple and efficient ASCII-Compatible Encoding (ACE). It transforms a Unicode string into a string of characters allowed in hostname labels (ASCII letters, digits and hyphens) and back again.

Use this tool to make conversions to and from Punycode. For best results, enter a fully qualified domain name (for example, www.domain.org). Remember to include the IDN domain prefix "xn--" if you are translating from Punycode.

IDNA Converter

See RFC3490, RFC3491, RFC3492 and RFC3454
This converter allows you to transfer domain names between the encoded (Punycode) notation and the decoded (UTF-8) notation.
Just enter the domain name in the respective field and click on the button right below it to have it converted. Please note, that you may enter complete domain names (like jürgen-müller.org) or an email address.
Make sure, that your browser is capable of the UTF-8 character encoding.
To ensure, that a certain string has been converted correctly, you should convert it both ways and compare the results.
Original (Unicode) Punycode (ACE)