Domain Availability Checker — RDAP, WHOIS & DNS JSON

Check whether a domain name is available to register or already taken. One JSON row per name: available/taken, registrar, created/expiry dates, name servers. Online, by API, or as an agent tool via Apify MCP.

This Actor asks the registry first (RDAP via the IANA bootstrap), then WHOIS, and records DNS as corroboration. It never marks a name available: true from a missing A record alone — that is how parked and quirky ccTLDs fake a vacancy.

What you get

• available / status — true/available or false/taken. Unknown lookups are {ok:false} and not charged.
• source — rdap, rdap-404, or whois (the evidence that produced the verdict)
• registrar, createdAt, expiresAt, nameServers — filled on taken names when the registry returns them
• dnsHasNs / dnsHasA — extra signal, never the sole verdict
• Bulk — up to 100 domains per run (default cap 25)
• Fail-soft — a dead WHOIS server or an invalid string never fails the run

Common requests this handles

Phrased the way people actually ask, so a buyer — or an AI agent choosing a tool — can match on the real requirement rather than the category name:

• "Is this domain available to register?" One row per domain with an explicit available / taken verdict, not a raw record you have to interpret.
• "Bulk domain availability check for a list of names." Pass up to 25 domains per run; each becomes its own record.
• "Check domain availability without a registrar API key." No registrar account, no API key, no reseller signup — RDAP and DNS are queried directly.
• "Who is the registrar and when does it expire?" Registrar, creation, expiry and update dates and nameservers come back on the same row as the verdict.
• "RDAP lookup as clean JSON." RDAP is the modern replacement for WHOIS; the response is parsed into flat fields rather than returned as raw text to regex yourself.
• "WHOIS fallback when RDAP has no data." WHOIS is used as a fallback, and the source field always says which one answered.
• "Domain research for brainstorming or brand checks." Invalid names and genuinely indeterminate answers are returned as such and are never charged.

Input

{ "domains": ["google.com", "a-name-you-hope-is-free.com"], "maxDomains": 25 }

Or a single name: { "domain": "google.com" }. URLs are accepted; scheme and path are stripped.

A programmatic {} run checks google.com (the schema default) so Apify's own listing test produces a real taken-domain row.

Output (real RDAP, trimmed)

{
  "domain": "google.com",
  "ok": true,
  "available": false,
  "status": "taken",
  "source": "rdap",
  "registrar": "MarkMonitor Inc.",
  "createdAt": "1997-09-15T04:00:00.000Z",
  "nameServers": ["ns1.google.com", "ns2.google.com"],
  "tld": "com"
}

Pricing

$0.02 per domain with a definite verdict. No start fee. Invalid names and lookup failures are recorded free.

Measured against the store leader on 2026-08-27: automation-lab/domain-availability-checker charges $0.035 to start plus about $0.002 per domain. A one-name check here is $0.02; there is no start tax. High-volume investor dumps at $0.002/name are a different product — this listing is the 1–25 name brand check.

Honest limits

• Not a suggestion engine. You pass exact names. It does not invent alternatives or check trademarks.
• Not aftermarket pricing. Taken names are taken; we do not quote GoDaddy/Sedo resale.
• Some ccTLDs have no RDAP. Those fall through to WHOIS. If both fail, you get {ok:false} uncharged rather than a guessed vacancy.
• .ai and similar TLDs: missing DNS is not availability. Those names are confirmed via WHOIS before available: true.

FAQ

How is this different from WHOIS Lookup? WHOIS Lookup (eliai/whois-lookup) answers "who holds this name?". This Actor answers "can I register it?" and includes registration fields on taken names. Different store query, different charge.

Will a 404 from DNS mean the name is free? No. Parking, registry wildcards, and several ccTLDs (.ai among them) lie that way. Available requires RDAP 404 or a registry WHOIS "not found".

What does a {} run return? google.com, taken, with registrar fields. That is the venue acceptance demo.

Why did a row come back ok: false? The name was invalid, or RDAP and WHOIS both failed to produce a verdict. Recorded with the error, never charged. Retry, or check the TLD still has a public registry.

Can I check 1,000 names? Cap is 100 per run (default 25). Split batches. At $0.02 each, 100 definite verdicts cost $2.00.

Use from code or AI agents

curl -s "https://api.apify.com/v2/acts/eliai~domain-availability-checker/run-sync-get-dataset-items?token=$APIFY_TOKEN" \
  -X POST -H "Content-Type: application/json" \
  -d '{"domains": ["yourbrand.com", "yourbrand.io"]}'

Store page: https://apify.com/eliai/domain-availability-checker

Changelog

• 0.1.0 (2026-08-27) — First public version. RDAP-first availability, WHOIS fallback, DNS corroboration only, $0.02 per definite verdict, no start fee.