An internationalised domain can have a readable Unicode form and an ASCII form used by many registration and DNS interfaces. Record both so you can recognise the same domain consistently across the client area, DNS tools and support requests.
IN THIS ARTICLE
01 Understand the two representations
The Unicode label is called a U-label. Its encoded ASCII equivalent is an A-label and commonly begins with xn--. For illustration, bücher.example corresponds to xn--bcher-kva.example. The reserved .example suffix here is for documentation.
Encoding does not make every Unicode string eligible for registration. The registry's supported scripts, character rules and variant policy still apply. A browser can display the ASCII form for security or compatibility reasons without changing the registered domain.
02 Check before ordering or editing DNS
- Confirm that the actual extension and ordering service support the intended language and characters.
- Use a trusted IDNA-aware conversion tool and compare the readable and ASCII forms carefully.
- Check availability and price for that exact domain. Watch for visually similar characters from another script.
- Record the accepted ASCII form in the order and domain inventory.
- When a DNS or API field requires ASCII, supply the complete encoded domain in the format that field documents.
Why does a copied name fail in an API or certificate request?
The receiving field may require the A-label form, reject unsupported characters or enforce the registry's policy. Copying from a formatted document can also introduce spaces or a different character that merely looks similar. Compare the exact string with the registered name and the field's documented format.
Use read-only DNS queries with the ASCII form to remove display ambiguity during diagnosis. Check the complete certificate hostname list and application configuration, not only the visible address bar. Never register a guessed replacement while an existing order is still uncertain.
Before advertising the domain, test the applications that customers will use, including email, forms, payment systems and password-reset messages. Registration support and end-to-end application support are separate checks.