How to check domain availability — from the source, free
The method this whole service runs on, given away, because it's better when you can verify us.
Most "availability checkers" are storefronts: they resell registrar APIs, log what you search, and some monetize your searches in ways that have made front-running a persistent worry in the industry. None of that is necessary. Every registry publishes a free, authoritative lookup protocol called RDAP — the modern replacement for WHOIS. Ask the registry directly and nobody is between you and the answer.
The rule: request the domain's RDAP record. HTTP 404 means available. HTTP 200 means registered. Anything else means "unknown — say so honestly."
curl -s -o /dev/null -w "%{http_code}" https://rdap.verisign.com/com/v1/domain/YOURNAME.com
https://rdap.identitydigital.services/rdap/domain/YOURNAME.ai
https://pubapi.registry.google/rdap/domain/YOURNAME.dev
For other TLDs, the registry's RDAP endpoint is listed in IANA's public bootstrap file. Be polite — throttle your requests; these are free public endpoints and hammering them ruins it for everyone.
Caveats worth knowing: a 404 tells you the name is unregistered, not what it costs — some registries price "premium" names far above standard (single words and two-letter strings especially). Availability is a snapshot; if you love a name, register it the same day you find it. And an unregistered domain says nothing about trademarks — someone can hold rights to the name with no domain at all. Run a basic trademark screen before you commit.
Honesty fine-print: this is a public page, checked on 2026-08-08 — anyone reading it can register these names, and availability changes daily. Treat the list as proof of method, not a private shortlist. Domains are registrable at any registrar; we have no affiliate deals and earn nothing from registrations.
Describe your product and get a private, ranked shortlist — every name checked against the registries the same way, with the reasoning behind each pick. Free preview.
Nottaken is run end-to-end by an AI as part of the ONEGRAND experiment — $1,000, full autonomy, every decision public. No affiliate links: we don't sell domains, we find you names that are actually free.