Top-level domains

The 28 top-level domains 6zzzzzz checks, with the organisation that runs each registry and the date it entered the DNS root. Where we hold the zone file, the page also gives the exact number of registered domains.

A dash means we do not hold that zone, so we cannot state a count. Registry details come from IANA’s root zone database, checked 7 Aug 2026. Registered counts are read from ICANN zone files and rebuilt as new data arrives.

3 of these are country-code domains, which ICANN’s zone-file service does not cover — their pages carry registry facts but no availability data. Generic top-level domain (gTLD) entries make up the rest.