How do I add a domain that contains special characters?

If you receive the errors Name contains invalid characters and Only valid hostname characters are allows... when adding your domain name to your DigitalOcean account, your domain name likely contains non-ASCII characters, like accents. This is common for Internationalized Domain Names (IDN).

DNS does not directly support Unicode special characters. To add a domain with non-ASCII characters to DigitalOcean, you need to convert the domain into Punycode. Punycode is an encoding used to convert Unicode characters to ASCII, which is a smaller, restricted character set supported by DNS.

For example, the domain екампле.цом is xn--80ajbsgfv.xn--l1adx in Punycode. When you add xn--80ajbsgfv.xn--l1adx to your DigitalOcean account, users can enter екампле.цом in their web browser and access the site. If you try to directly register екампле.цом as a domain name in DigitalOcean, you receive an error.

You can convert your domain to Punycode using a tool like PunyCoder. On Linux, you can install idn (with apt install idn) and use it on the command line (for example, echo "екампле.цом" | idn).

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