Domain Availability Checker: Bulk RDAP Lookup

This domain availability checker tells you, for hundreds of domains at once, whether each one is registered or free. It asks each registry's official RDAP server (the modern replacement for WHOIS), so a registered domain also comes back with its registrar, creation and expiry dates, status codes and nameservers. Give it a list of domains, or a list of names plus a list of TLDs and it checks every combination. No API key or registrar account needed.

• Names times TLDs. acme and getacme with com, io, ca and ai gives 8 checks in one go.
• Straight from the registry. The RDAP server for each TLD comes from IANA's official bootstrap file, so answers come from Verisign for .com, CIRA for .ca, Nominet for .uk and so on, not from a reseller's cache.
• Honest about the gaps. Some TLDs (.io, .co, .de and others) have no RDAP server. For those the Actor checks DNS instead and says so in method and confidence.
• Expiry watch. daysToExpiry and pendingDelete show which registered domains are about to lapse.

What data you get

Field	What it holds
domain, name, tld	The domain and its two parts (domainAscii holds the punycode form of names like bücher.de)
available, status	true / available when the registry has no record, false / registered when it does
method, confidence	rdap with high confidence, or dns with high, medium or low for TLDs without RDAP
registrar, registrarIanaId	Who the domain is registered through
createdAt, updatedAt, expiresAt, daysToExpiry	Registration, last change and expiry dates, and days left until expiry
statusCodes	Registry status codes such as client transfer prohibited, redemption period or pending delete
nameservers	Nameservers of a registered domain
premium, reserved, pendingDelete, note	Flags when the registry's answer mentions them, with a plain-language note
rdapServer, source, checkedAt	Which server answered, which input the check came from, and when

How to use it

1. Add full domains, or names plus TLDs, or both.
2. Set Max checks so a big names-times-TLDs list can't grow beyond what you want to pay for.
3. Run it and export to JSON, CSV or Excel, or call it from the API, Make, Zapier, n8n or an AI agent through the Apify MCP server.

The Actor checks up to 12 domains at a time but never more than 2 at once against the same registry, and it backs off when a registry answers "Too Many Requests". In our test, 321 domains across 8 TLDs took about one minute.

Example input

{
  "domains": ["apify.com"],
  "names": ["acme", "getacme"],
  "tlds": ["com", "io", "ca", "ai"],
  "maxChecks": 50
}

Example output (three of the nine results)

A registered domain, answered by Verisign's RDAP server:

{
  "domain": "acme.com",
  "domainAscii": "acme.com",
  "name": "acme",
  "tld": "com",
  "available": false,
  "status": "registered",
  "method": "rdap",
  "confidence": "high",
  "registrar": "eNom, LLC",
  "registrarIanaId": "48",
  "createdAt": "1991-04-17T04:00:00.000Z",
  "updatedAt": "2026-04-17T09:07:22.000Z",
  "expiresAt": "2027-04-18T04:00:00.000Z",
  "daysToExpiry": 170,
  "statusCodes": ["client transfer prohibited"],
  "nameservers": ["ns1.hover.com", "ns2.hover.com"],
  "premium": null,
  "reserved": null,
  "pendingDelete": false,
  "note": null,
  "rdapServer": "rdap.verisign.com",
  "inputDomain": null,
  "source": "acme x com",
  "checkedAt": "2026-10-30T02:39:36.849Z"
}

A free domain, answered by the .ai registry:

{
  "domain": "getacme.ai",
  "available": true,
  "status": "available",
  "method": "rdap",
  "confidence": "high",
  "registrar": null,
  "expiresAt": null,
  "statusCodes": [],
  "nameservers": [],
  "rdapServer": "rdap.identitydigital.services",
  "source": "getacme x ai"
}

A .io domain, where only DNS could be checked:

{
  "domain": "getacme.io",
  "available": true,
  "status": "available",
  "method": "dns",
  "confidence": "low",
  "note": "dns-only, not certain: this TLD has no RDAP server and the name has no DNS records. It may still be registered without nameservers, reserved or premium. Check at a registrar.",
  "rdapServer": null,
  "source": "getacme x io"
}

How much does it cost?

You pay per domain with a result: $0.002 per domain, plus $0.0005 once per run. 1,000 domains cost about $2.00. Apify's free plan credit of $5 a month covers about 2,500 checks.

Invalid names (a space, a TLD that does not exist) and lookups that fail are free. They are listed with the reason in the SUMMARY record of the run's key-value store.

Use cases

• Naming a startup or product: try 30 name ideas against the 6 extensions you care about in one run.
• Brand protection: check which variants and country extensions of your brand are still open.
• Expiring domain watch: run your list on a schedule and sort by daysToExpiry, or filter on pendingDelete.
• Portfolio audit: pull registrar, expiry and nameservers for every domain your company owns.
• Lead research: see who registered a set of domains, and when.

FAQ

Does "available" mean I can buy it at the normal price? No. available: true means the registry has no record of the domain. Premium pricing, registry reservations and registrar-specific rules are not part of RDAP for most registries, so premium and reserved are only set when the registry's answer mentions them, and null does not mean "normal price". Always check the price and final availability at a registrar before you count on a name.

Which TLDs have no RDAP server? As of October 2026, IANA's bootstrap file has no RDAP server for, among others, .io, .co, .me, .de, .eu, .us, .jp, .es, .it, .ch, .se, .be, .at, .mx, .ru, .cn, .gg, .so and .sh. The Actor reads the bootstrap file fresh on every run, so new RDAP servers are picked up on their own. For these TLDs it checks DNS:

• Nameservers found: registered, confidence: "high".
• The name exists in DNS but its nameservers fail or are missing: registered, confidence: "medium".
• No DNS records at all: available: true with confidence: "low" and a note, because a domain can be registered without nameservers.

Registrar and dates are not available through DNS.

How accurate is the RDAP result? It is the registry's own answer at the time of the check: HTTP 404 means not registered, a domain record means registered. A domain that was just deleted, or is in a drop or auction, can still change minutes later.

What happens with subdomains and URLs? They are trimmed to the registrable domain using the public suffix list, so https://www.bbc.co.uk/news is checked as bbc.co.uk and the original is kept in inputDomain.

Will registries block me? Registries limit how fast one IP can ask. The Actor keeps at most 2 requests in flight per registry, spaces them out, and pauses that registry when it answers 429. In our 321-domain test, Google's registry asked for a few short pauses and every check still finished. If a huge run keeps getting 403 or 429, turn on Apify Proxy.

Is this legal? RDAP is the public lookup service that ICANN requires of generic TLD registries, and many country registries run it too. Most registries redact registrants' personal data themselves.

Other Actors by this developer

• Domain Profile: WHOIS and DNS: full WHOIS, DNS records and age for domains that are already registered.
• Website Tech Stack Detector: see what a registered domain's website runs on.
• Email Security Audit: SPF, DKIM, DMARC: check a domain's email setup.
• Website Change Monitor: get told when a page on a domain changes.