Callook: USA Amateur Radio Callsign Lookup

Callook provides a no-nonsense amateur radio U.S.A. callsign lookup service. The database is current as of March 22, 2026. Users can search for valid callsigns to retrieve information. The service offers multiple views, including a browser search plugin, API access with a reference, and plain text output. Geographic coordinates are provided by the Bing Maps API, and the grid square is mathematically calculated from these coordinates. The accuracy of coordinates and grid squares is not guaranteed due to reliance on an external service. Callook is maintained by Josh Dick, W1JDD, and is built using valid HTML5. Donations are accepted to help with hosting costs.