IDN domains with æøå are supported in modern browsers, but can cause e‑mail problems, so we recommend using an ASCII domain and forwarding the IDN version.
IDN domains (domains with special characters) are a little different in their use compared to normal domains.
Most web browsers such as Mozilla Firefox, Google Chrome, Apple Safari and Microsoft Internet Explorer 7+ / Edge have built‑in support for IDN domains, and therefore require no special configuration to visit the domain. In general you do not need to worry about a lack of IDN support as you might have in the “old days”.
However, when it comes to e‑mail the most important thing is that the sender’s computer/software supports IDN domains. Microsoft Outlook 2007 and newer understand the use of IDN domains in e‑mail addresses, but there can be issues with older and other mail programmes, such as web‑mail and mail on iPhone.
Because of the above circumstances we always recommend buying a domain without æøå and then linking any æøå domain to the primary domain via your control panel. For example aeble.dk and æble.dk. This ensures that people can send mail to you at aeble.dk while still being able to view your site if they choose to use æble.dk.
Technically an IDN domain can also be written as an xn-- string, for example æble.dk is written as xn--ble-xla.dk. If you use the xn-- string an IDN domain will always work, in all programmes and in all respects. Often the xn-- string is therefore used in various places. E.g. if you share a link to the site on Facebook, the xn-- string will be used for the domain.
Article from the support category: Domain & DNS
