Domain & App-Name Availability

base /domain-availability/v15 endpoints

post/domain-availability/v1/check1 credit

Is one domain available? Combined RDAP and DNS verdict with confidence + Domainr-style status tokens + a register_url when free. Accepts domain OR name+tld.

Parameter		Allowed / range	Description
domain	required	—	A full domain to check (e.g. myapp.com, my-startup.io). A bare host, a full URL, or a leading www. are all accepted and normalized.
name	optional	—	A bare app/brand name label (e.g. 'myapp', 'My Startup' → 'my-startup'). Spaces/underscores become hyphens; the TLD is added separately via 'tlds'.
tld	optional	—	TLD to combine with 'name' if no full 'domain' is given.
signal = both	optional	both · rdap · dns	Which availability signal(s) to use. 'both' (default) is the most accurate: RDAP for registrar-grade facts + DNS to disambiguate TLDs that have no RDAP server (io/co/me).
whois = false	optional	—	If true and the domain is registered, also attach the full WHOIS/RDAP record (registrar, dates, nameservers, status) inline.
include_pii = false	optional	—	If true, return the full RDAP registrant contact. Default false → personal data dropped (GDPR), organization kept.

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post/domain-availability/v1/bulk_check1 credit

One NAME across many TLDs → availability map (which of name.com/.io/.ai/… are free).

Parameter		Allowed / range	Description
name	required	—	A bare app/brand name label (e.g. 'myapp', 'My Startup' → 'my-startup'). Spaces/underscores become hyphens; the TLD is added separately via 'tlds'.
tlds	optional	com · net · org · io · co · app · dev · ai · me · xyz · tech · io	TLDs to check (comma-separated string or array, with or without a dot). Defaults to com,net,org,io,co,app,dev,ai,me,xyz. Any valid TLD label is accepted (not just the suggested list); capped at 60.
signal = both	optional	both · rdap · dns	Which availability signal(s) to use. 'both' (default) is the most accurate: RDAP for registrar-grade facts + DNS to disambiguate TLDs that have no RDAP server (io/co/me).

Try in playground →

post/domain-availability/v1/rdap1 credit

Full WHOIS via RDAP for a registered domain (registrar, created/expires, status, nameservers, dnssec, abuse). A 404 is returned cleanly (available on RDAP-served TLDs; null + a pointer to 'check' on TLDs with no RDAP server), not an error.

Parameter		Allowed / range	Description
domain	required	—	A full domain to check (e.g. myapp.com, my-startup.io). A bare host, a full URL, or a leading www. are all accepted and normalized.
raw = false	optional	—	If true, also attach the raw upstream RDAP JSON under whois.raw_rdap.
include_pii = false	optional	—	If true, return the full RDAP registrant contact. Default false → personal data dropped (GDPR), organization kept.

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post/domain-availability/v1/suggest1 credit

Name variations (prefix/suffix/TLD permutations, deterministic — no LLM) each with a live availability verdict; available ones surfaced first.

Parameter		Allowed / range	Description
name	required	—	A bare app/brand name label (e.g. 'myapp', 'My Startup' → 'my-startup'). Spaces/underscores become hyphens; the TLD is added separately via 'tlds'.
tlds	optional	com · net · org · io · co · app · dev · ai · me · xyz · tech · io	TLDs to check (comma-separated string or array, with or without a dot). Defaults to com,io,ai,app,dev,co. Any valid TLD label is accepted (not just the suggested list); capped at 60.
signal = both	optional	both · rdap · dns	Which availability signal(s) to use. 'both' (default) is the most accurate: RDAP for registrar-grade facts + DNS to disambiguate TLDs that have no RDAP server (io/co/me).

Try in playground →

post/domain-availability/v1/batch1 credit

Many DIFFERENT full domains in one call → availability for each (bulk check).

Parameter		Allowed / range	Description
domains	required	—	A list of FULL domains to check at once (comma-separated string or array). Capped at 100 per call; invalid entries are reported under 'invalid'.
signal = both	optional	both · rdap · dns	Which availability signal(s) to use. 'both' (default) is the most accurate: RDAP for registrar-grade facts + DNS to disambiguate TLDs that have no RDAP server (io/co/me).

Try in playground →

Example request · check

curl -X POST https://api.reefapi.com/domain-availability/v1/check \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"domain":"google.com"}'

Response shape

{
  "ok": true,
  "data": { /* the result */ },
  "meta": {
    "latency_ms": 240,
    "record_count": 12,
    "completeness_pct": 100
  },
  "error": null
}

Built for volume

5M+ requests a day

Measured at 60 requests a second across the fleet, with no central bottleneck. Volume pricing is on request, and per-key limits are raised for high-volume accounts.

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