Domain WHOIS & DNS Lookup via RDAP

Check registration and DNS before deciding whether to contact or inspect a domain. Get RDAP registration data, Cloudflare DNS records, email-provider hints and homepage evidence in one row. Registration uses RDAP, not the WHOIS protocol. Homepage redirects are reported without fetching the target. Each qualifying domain costs $0.00045, plus $0.00005 per run start at default memory.

Try it

{"domains":["example.com"]}

An empty input {} runs the same example. An empty domains list fails the run. No upstream API key is needed.

Use from an agent

Add https://mcp.apify.com?tools=miacx/domain-whois-dns-lookup to your MCP client and sign in to Apify. Call the dedicated Actor tool with the input above, then read its completed dataset with get-dataset-items. Or set APIFY_TOKEN to your Apify API token and request JSON rows:

curl --fail-with-body 'https://api.apify.com/v2/actors/miacx~domain-whois-dns-lookup/run-sync-get-dataset-items' \
  -H "Authorization: Bearer $APIFY_TOKEN" -H 'Content-Type: application/json' \
  -d '{"domains":["example.com"]}'

What you get

Read status first, then inspect errors and the source fields. A partial result can still be usable and billable. Rows arrive in completion order, one per unique normalized hostname. Match them using input or domain. status: "ok" means no source errors were recorded; unsupported RDAP or a skipped homepage can still occur.

Selected fields below come from recorded example.com fixtures, processed with the fixed test clock. The robots.txt 404 response is supplied by the test setup.

{
  "input": "example.com",
  "domain": "example.com",
  "status": "ok",
  "ok": true,
  "errors": [],
  "rdapStatus": "registered",
  "registrar": "RESERVED-Internet Assigned Numbers Authority",
  "createdAt": "1995-08-14T04:00:00Z",
  "expiresAt": "2027-08-13T04:00:00Z",
  "rdapFetchedAt": "2026-10-31T02:10:00.000Z",
  "mx": [{"priority":0,"exchange":""}],
  "emailProvider": "none",
  "spf": true,
  "dmarc": true,
  "dmarcPolicy": "reject",
  "homepageStatus": "fetched",
  "httpStatus": 200,
  "redirectTarget": null,
  "tech": [{"name":"Cloudflare","evidence":"server: cloudflare"}],
  "parked": false,
  "forSale": false,
  "parkingEvidence": []
}

Registration fields include the registrable domain, creation/expiry/change dates, registrar, IANA ID and domain status strings. rdapStatus is registered, not_registered for a registry 404, unsupported when no service is available, or null on failure. RDAP dates come from registry events; they are not fetch times. Registrant contacts are excluded.

DNS includes a, aaaa, mx, ns, txt and nxdomain. Record arrays retain resolver order. MX entries contain numeric priority and exchange; an empty exchange represents null MX. Null fields mean unknown or unavailable; empty record arrays mean the query returned no matching records. emailProvider is inferred from the preferred MX, with none for no usable MX and other for unrecognized hosts. SPF and DMARC fields report observed records, not a complete email-security assessment.

tech contains deduplicated name/evidence pairs from headers and HTML signatures. parked and forSale are true when a matching signal exists, false after complete 2xx HTML analysis finds none, or null. parkingEvidence lists observed signals; an empty list does not prove the domain is available to buy.

rdapFetchedAt and homepageFetchedAt mark response receipt; dnsFetchedAt marks the start of the query set. Cache hits preserve those timestamps. rdapCached and dnsCached identify cache reuse.

Input

Field	Default	Accepted input
domains	["example.com"]	1–10,000 domains, hostnames, URLs or email addresses. Null also uses the default at runtime.
maxConcurrency	8	Integer from 1 to 20. Upstream requests are capped at twice this number.

Inputs are trimmed, lowercased and IDNA-converted. URLs and emails contribute only their hostnames. Subdomains remain distinct results; RDAP uses their ICANN registrable domain. Private suffixes do not change the registry lookup; foo.github.io uses github.io for RDAP. Invalid entries return error rows rather than failing the batch.

Pricing

A Domain event (domain-result) costs $0.00045 per unique normalized hostname with a qualifying source answer. It counts an RDAP registered/not-registered answer, a DNS hostname or DMARC answer, or a homepage HTTP response. Partial results, negative answers and cached answers count. Homepage responses can qualify even with non-2xx HTTP status. Invalid inputs and total source failures incur no Domain events. Duplicate hostnames incur no additional events within one run.

1,000 qualifying domains cost $0.45005, including the $0.00005 run start at default 256 MB memory. The start charge applies even with no billable domains. Apify counts one start event per GB, with a minimum of one. Processing stops at the charge limit; remaining domains may have no rows.

Limits and data freshness

• Each input allows 1,024 characters; hostnames allow 253. IP addresses and bare public suffixes are rejected.
• Homepage checks request HTTPS on port 443 and respect robots.txt. Private and reserved addresses are blocked.
• Homepage HTML is capped at 256 KiB, robots.txt and RDAP at 512 KiB, and each DNS response at 64 KiB.
• No browser rendering or runtime LLM calls run. Redirect targets need a separate input to inspect their homepage.
• RDAP redirects and registrar follow-up services are not queried. DMARC checks only _dmarc on the supplied hostname.

The Actor caches RDAP answers and the IANA bootstrap in memory for the duration of a run. Registered answers and bootstrap data can be reused for 24 hours; not-registered answers for one hour. Stored entries remain until overwritten or deleted; expiry controls reuse. DNS uses the shortest observed TTL, capped at one hour, and only caches complete successful query sets. Homepage results and robots decisions can be reused for five minutes. DNS and homepage caches last only within the run.

The synchronous API waits up to 300 seconds. Use asynchronous runs for longer batches.

If a row fails

Each errors entry has source, code and message, ordered by input, RDAP, DNS, then homepage. Correct INVALID_DOMAIN; avoid private hosts for HOST_NOT_PUBLIC. Retry RATE_LIMITED, TIMEOUT, NETWORK_ERROR, DNS_QUERY_FAILED or ROBOTS_UNAVAILABLE after checking the source message. Inspect UPSTREAM_ERROR, INVALID_RESPONSE, RESPONSE_TOO_LARGE and INTERNAL_ERROR before retrying. Reduce work if BUDGET_EXHAUSTED occurs. Successful source fields remain available alongside errors.