Reverse Dns Lookup API

Network tool

POST https://api.findutils.com/api/tools/reverse-dns-lookup/execute

Look up the reverse DNS (PTR) hostname of an IPv4 or IPv6 address through a public DNS-over-HTTPS resolver. Returns the in-addr.arpa or ip6.arpa name queried, the response code and every PTR hostname with its TTL; found is false when there is no PTR record (NXDOMAIN or an empty answer).

Needs an API key. Running a tool needs an API key. Keys are not for sale yet: ask for early access. About API keys

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Request body

application/json

ip

string required

IPv4 or IPv6 address, e.g. "8.8.8.8" or "2001:4860:4860::8888".
resolver

string optional

Public resolver to ask: google (dns.google) or cloudflare (cloudflare-dns.com). One of google · cloudflare. Default "google".

Example arguments

Verified

{
  "ip": "8.8.8.8"
}

curl -X POST https://api.findutils.com/api/tools/reverse-dns-lookup/execute \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "ip": "8.8.8.8"
  }'

const response = await fetch('https://api.findutils.com/api/tools/reverse-dns-lookup/execute', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json', Authorization: 'Bearer YOUR_API_KEY' },
  body: JSON.stringify({"ip":"8.8.8.8"}),
});
const data = await response.json();

import requests

response = requests.post(
    "https://api.findutils.com/api/tools/reverse-dns-lookup/execute",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={"ip":"8.8.8.8"},
)
data = response.json()

$ch = curl_init('https://api.findutils.com/api/tools/reverse-dns-lookup/execute');
curl_setopt_array($ch, [
    CURLOPT_POST => true,
    CURLOPT_HTTPHEADER => ['Content-Type: application/json', 'Authorization: Bearer YOUR_API_KEY'],
    CURLOPT_POSTFIELDS => '{"ip":"8.8.8.8"}',
    CURLOPT_RETURNTRANSFER => true,
]);
$data = json_decode(curl_exec($ch), true);

Also an MCP tool

Call reverse_dns_lookup from Claude, Cursor or any MCP client. Same arguments, same output.

https://mcp.findutils.com

MCP reference

Rate limit: 60 a minute, per IP
Auth: API key
REST id: reverse-dns-lookup
MCP name: reverse_dns_lookup
Category: Network
Machine-readable: openapi.json · markdown.md

This tool fetches a fixed, hard-coded public upstream, never a private host. Results depend on that upstream.

Request body

Example arguments

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