With the IDN Converter you can convert IDNs into the ACE string and vice versa.
How do IDNs work?
To ensure that IDNs also work for the DNS servers, a suitable procedure was developed during their introduction. The Unicode character string (IDN notation) is converted into a valid ASCII character string using the Punycode coding procedure. This converted character string is called an ACE string (ACE = ASCII Compatible Encoding). The ACE string is then stored in the DNS.