DNS (Domain Name System) is a key part of the internet: it maps human-readable domain names (like to the corresponding numeric IP address (like The servers that do this mapping are called resolvers.
Open DNS Resolvers

You do not have to use your ISP's DNS resolver. Here are some alternatives that may better suit your needs.

Geolocation Icon Your Nameservers


Your IP Icon Your IP Address
Reverse DNS:

Geolocation Icon Your Location

IP Geolocation uses your IP address to guess your approximate location.
Your location: Ashburn, United States: 39.0469, -77.4903

DNS Lookup Icon DNS Lookups

Lookup a hostname across all the open resolvers

Reverse DNS Icon Reverse DNS Lookup

Given an IP address, find the corresponding hostname

Tools Icon Tools

Random tools I made that needed a good home.


Most of the pages have a corresponding JSON and/or text endpoint that you can call.

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