Free tool · Hosted domains

Reverse IP lookup

Enter an IPv4 address to list the domains that point to it. The free lookup uses the ipbase hosted domains endpoint, which is on the Medium plan and above.

Typical uses

Security investigations, finding sites on the same shared host, checking your own server and competitive research.

Building this into an app? Use the Reverse IP API and its domains endpoint documentation.

Hosted domains by API

curl "https://api.ipbase.com/v2/domains?ip=1.1.1.1" -H "apikey: YOUR-API-KEY"

Frequently asked questions

What is a reverse IP lookup?

It lists the domain names whose DNS records point to an IP address. On shared hosting, hundreds of websites can share one address.

Is a reverse IP lookup the same as reverse DNS?

No. Reverse DNS (PTR) returns the one hostname the network owner set for the address. A reverse IP lookup returns all domains that point to it.

IP geolocation API

Get this data in your app

ipbase returns location, ISP, ASN and time zone for any IPv4 or IPv6 address, up to 1,000 addresses per POST request. Security flags (VPN, proxy, Tor, data center) are on the Small plan and above.

Read the documentation

150 free requests every month. No credit card required.

GET https://api.ipbase.com/v2/info?ip=1.1.1.1

{
  "data": {
    "ip": "1.1.1.1",
    "type": "v4",
    "connection": {
      "asn": 13335,
      "organization": "APNIC and Cloudflare DNS Resolver project",
      "isp": "Cloudflare, Inc",
      "range": "1.1.1.0/24"
    },
    "location": {
      "country": { "alpha2": "AU", "name": "Australia" },
      "zip": "4000"
    },
    "security": { "is_vpn": null, "is_tor": null, "threat_score": null }
  }
}

Free IP tools

ASN lookup Owner and prefixes of any AS number. Bulk IP lookup Up to 100 IPs at once, CSV export. IP address converter Decimal, hex, binary, IPv4↔IPv6. IP address lookup Location and owner of any IP. IP range to CIDR converter Ranges to CIDR blocks and back. Subnet calculator CIDR, netmask and host range. VPN and proxy checker VPN, proxy and Tor flags of any IP. What is my IP address? Your public IP, location and provider. What is my ISP? Which internet provider you use. Cloud & bot IP rangesOfficial lists of AWS, Googlebot, GPTBot and more.

Example lookups: 8.8.8.8 · 8.8.8.0/24 · AS15169 · example.com · all IPv4 ranges