A simple DNS lookup tool
Domain 1.1.1.1
Type PTR
Server Cloudflare
Duration 4 ms
Results
JSON ZONE 
{
  "status": "NOERROR",
  "from": "1.1.1.1",
  "answer": [
    {
      "type": "PTR",
      "name": "one.one.one.one",
      "ttl": 544
    }
  ]
}
This Lookup
Realtime Lookup