Domain availability checked against real zone data

6zzzzzz answers one question quickly: is this name taken, and if it is, what near it is free? Availability comes from the actual zone files ICANN publishes through its Centralized Zone Data Service, not from a registrar’s inventory, so the answer reflects what is really in the DNS. We currently hold 225,551,598 registered domains across 25 zones, last built 23 Sept 2026.

Every lookup is an exact match against the whole corpus held in memory, which is why results arrive in well under a millisecond and why nothing is sampled or approximated. There is no account, no sign-up, no rate limit and no paid tier.

Browse the 28 top-level domains we cover for registry details and how many domains each one holds.