IP lookup and geolocation

The IP lookup page geolocates any IPv4 or IPv6 address: country, city, ASN, ISP, reverse DNS, and a blacklist count. The homepage shows the public address of the connection you are using now. Country pages are listed under IP by country. Bulk lookup takes a list of addresses. ASN lookup names the network that announces an address. How IP geolocation works explains why the city is often wrong.

Geolocation databases map a prefix, not a street. The subnet calculator turns a prefix into its mask, wildcard, and host range. The CIDR calculator converts a prefix to a range and an IPv4 range back to CIDR blocks.

From a terminal, the commands are on the CLI page. The same lookup is the no-key JSON API, on the API page and the API docs.

The other groups are leak tests, network diagnostics, and email and domain security.