AreaCodeBook.com is an online reference for finding telephone area codes across the United States, Canada, and other locations in the North American Numbering Plan. Its directory organizes area codes by their numerical prefixes, making it easy for visitors to browse codes or look up a location. Users can search by area code or place and filter the listings by number range, from 2xx through 9xx.

The site presents a broad directory covering 469 area codes, with entries that pair each code with a state, province, territory, country, or service designation. Listings include locations throughout the United States and Canada, as well as Caribbean nations and territories. The directory also identifies special categories such as non-geographic services, Canadian non-geographic services, NANP area codes, and US Government use. AreaCodeBook.com is designed as a straightforward information resource for people who want to identify where a number’s area code is associated or find codes for a particular location.