Punycode Converter
Convert internationalised domain names to ASCII and back, with homograph warnings.
About this tool
Converts domain names between their Unicode form and the ASCII form DNS actually uses — `münchen.de` and `xn--mnchen-3ya.de` are the same domain.
It also checks for homograph risk. A domain written in Cyrillic characters that look exactly like Latin ones is the mechanism behind a well-known class of phishing domain, and mixing scripts within one label is almost always either a mistake or an attack. If you are converting domains in bulk, you want to be told which ones are not what they appear to be.
Common questions
What is Punycode?
The encoding that lets a domain containing non-ASCII characters be represented in the ASCII that DNS requires. It always starts with the prefix xn--, which is how you recognise one.
Why does my browser show xn-- in the address bar?
A deliberate safety measure. Browsers display the ASCII form when a domain mixes scripts or uses a script that is not among your languages, precisely so a lookalike cannot pass as a familiar name.
What is a homograph attack?
Registering a domain that looks identical to a real one by substituting characters from another script — a Cyrillic "а" for a Latin "a". The two are different domains that render the same. This tool flags them.
Is an IDN bad for SEO?
No. Search engines handle both forms and treat them as one domain. The real cost is human: people mistype them, and some software still mangles the ASCII form.