WHOIS lookup: who owns a domain

$0.01 per call · failed calls are never charged · no account or subscription: pay per call with a card key or USDC

WHOIS lookup for a domain: registrar, creation and expiry date and age (RDAP/WHOIS), plus its DNS records and email setup (SPF, DMARC). Use to check who registered a domain, how old it is and where it is hosted, for lead research and phishing checks.

Run it free (25 free calls) Buy credits by card (from $1) Example result (JSON)

Try it with your own inputs

Domain name, e.g. cloudflare.com

Uses one of your 25 free calls. Nothing is charged, and a call that fails is not counted.

Inputs

NameTypeDescription
name (required)stringDomain name, e.g. cloudflare.com

Request

Over HTTP, with a card key from /credits:

curl -H "Authorization: Bearer adt_…" "https://tools.funwords.eu/whois/lookup?name=cloudflare.com"

Or one of your 25 free calls, no key:

curl "https://tools.funwords.eu/whois/lookup?name=cloudflare.com&trial=1"

Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum or Solana over x402; Base or Tempo over MPP) and retries.

Example result

{
  "domain": "cloudflare.com",
  "exists": true,
  "dns": {
    "a": [
      "104.16.132.229",
      "104.16.133.229"
    ],
    "mx": [
      {
        "priority": 5,
        "host": "mxa-canary.global.inbound.cf-emailsecurity.net"
      }
    ],
    "ns": [
      "ns3.cloudflare.com",
      "ns4.cloudflare.com"
    ],
    "dnssecValidated": true
  },
  "email": {
    "acceptsMail": true,
    "spfPolicy": "-all",
    "dmarcPolicy": "reject"
  },
  "registration": {
    "registrableDomain": "cloudflare.com",
    "registrar": "Cloudflare, Inc.",
    "registeredAt": "2009-02-17T22:07:54Z",
    "expiresAt": "2033-02-17T22:07:54Z",
    "ageDays": 6441,
    "dnssecSigned": true
  }
}

From an AI agent (MCP)

Add the MCP server to Claude, Cursor or any MCP client. This tool is whois_lookup, and the first 25 successful calls are free:

https://tools.funwords.eu/mcp

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