IDN (Internationalized Domain Name) are domain names containing non-ASCII characters, such as the accented characters of Italian, the umlaut of German (ä), or the letter ô of French.

The domain name resolution standard (DNS) does not allow the use of these characters, however, through the conversion mechanisms now also adopted by the registry of Italian domains, it is possible to register Italian domains that also contain characters with accents or with some non-Latin characters, including:

à â ä è é ê ë ì î ï ò ô ö ù û ü æ œ ç ÿ

Accented domains are obviously different from those registered without accent: until today, the Italian web has registered these accented domains assuming that users would not insert accented letters. However, from now on, it will be easier to exploit them because people are used to type the domain including any accented letter.

What happens in the browser?

In some browsers it may happen that, after typing the domain with an accented character, this is converted into ASCII characters in the address bar: the domain has not changed but, since it can be reached both in its accented form and in ASCII encoding (as transformed by the browser), older browsers generally perform and display the transformation of the name into ASCII characters directly in the address bar.

Currently, however, most browsers (Firefox, Chrome, Opera, Edge) do not display this name transformation in the address bar, leaving the accented characters and therefore the domain name unchanged.

How it works

The IDNA (Internationalized Domain Names in Applications) system associates each character not supported by the DNS standard with a specific combination of ASCII characters.

The conversion takes place in the user’s browser, which translates non-ASCII characters into ASCII characters; therefore, for a converted domain to “work”, the user who surfs the web must have an up-to-date browser that is compatible with the new transcoding methods.

The real name of a domain with special characters will start with the prefix xn-- followed by the set of characters representing  the real name.

EXAMPLE The città.it domain written with non-ASCII characters will correspond the real name, xn--citt-3na.it.