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POST AI agent ready /v1/domain/availability

Domain Availability API - Check If a Domain Is Registered

Queries RDAP (the modern successor to WHOIS) for a domain and reports whether it is registered. Returns available: true when RDAP responds 404 and registered: true with the registrar name when a record exists. Works across all gTLDs and most ccTLDs supported by public RDAP servers.

Parameters

stringrequired

Fully qualified domain name to check (e.g., "example.com").

Code examples

curl -X POST https://api.botoi.com/v1/domain/availability \
  -H "Content-Type: application/json" \
  -d '{"domain":"botoi.com"}'

When to use this API

Domain-name suggestion tools

When a user types a product name, generate variant domain candidates (add -app, -hq, -io) and call this endpoint in parallel. Show only the ones with available: true.

Brand monitoring and defensive registration

Check typo-squatted variants of your brand domain on a schedule. Get notified the moment a lookalike registers so you can take action through UDRP or a cease-and-desist.

Bulk availability checks for portfolio resellers

Feed a list of candidate domains through this endpoint from a batch job. Combine available and registrar fields with your own valuation rules to surface expired or dropped domains worth acquiring.

Frequently asked questions

How does this differ from a WHOIS lookup?
RDAP is the IETF standard replacing WHOIS. It returns structured JSON instead of free-form text, supports HTTPS, and is the authoritative protocol for gTLD availability. This endpoint queries rdap.org, which aggregates registry and registrar RDAP servers.
Does available: true guarantee I can register the domain?
No. Available means no RDAP record exists. Some registries reserve names, block premium tiers, or enforce TLD-specific rules. Always confirm through your registrar before committing to a launch.
Which TLDs are supported?
All gTLDs (.com, .net, .org, .io, .app, etc.) and most ccTLDs with public RDAP servers. A few ccTLDs (such as .de or .it) restrict RDAP access; for those the endpoint may return an indeterminate response with a note field.
Is the registrar field always present?
No. The registrar is extracted from the RDAP entities array when a record with role "registrar" is found. Some registries omit this field for privacy or technical reasons.

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