Domain Availability APIs
Domain availability APIs check whether a name is free to register before you send a user to a registrar. DigMyName is free and keyless and also compares registrar prices across 50+ TLDs. WhoisXML API's checker, offered as a free trial, lets you choose between a fast DNS check and a slower DNS-plus-WHOIS/RDAP check. Domainr is listed but currently unavailable.
| API | Pricing | Auth | Format | Free tier | Status |
|---|---|---|---|---|---|
DigMyNameChecks domain availability and compares registrar prices across 50+ TLDs, no key required. Developer Tools › WHOIS & DNS | Free | None | JSON | 10k+/day | Live |
Domainr (Fastly)Domain name suggestions and registration status (available, parked, premium, for sale) across TLDs. Developer Tools › WHOIS & DNS | API key | JSON | — | Deprecated | |
WhoisXML API Domain AvailabilityChecks whether a domain is free to register, using a fast DNS check or a slower DNS-plus-WHOIS/RDAP check. Developer Tools › WHOIS & DNS | Free trial | API key | JSON | — | Live |
DigMyNameFreeLive
Checks domain availability and compares registrar prices across 50+ TLDs, no key required.
None · JSON
10k+/day
OpenAPI spec · llms.txt
Domainr (Fastly)Deprecated
Domain name suggestions and registration status (available, parked, premium, for sale) across TLDs.
API key · JSON
—
no machine-readable spec
WhoisXML API Domain AvailabilityFree trialLive
Checks whether a domain is free to register, using a fast DNS check or a slower DNS-plus-WHOIS/RDAP check.
API key · JSON
—
no machine-readable spec
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Choosing a Domain Availability API
Is there a free Domain Availability API?
Yes. DigMyName is free to use.
Which Domain Availability APIs work without an API key?
DigMyName needs no key or sign-up, so you can try it with a plain request.
Can I call a Domain Availability API from front-end JavaScript?
DigMyName allows cross-origin requests and needs no key, so it works straight from the browser. For the others, call them from your server so your key stays private.
Can I use Domain Availability APIs in a commercial project?
WhoisXML API Domain Availability permits commercial use.
Which Domain Availability APIs work with AI agents?
DigMyName publishes an OpenAPI spec for generating clients and tools.
Broader: WHOIS & DNS APIs · Developer Tools APIs
More in WHOIS & DNS: DNS Lookup APIs