Carfax, Inc. is a commercial web-based service that supplies vehicle history reports to individuals and businesses on used cars and light trucks for the American and Canadian marketplaces.

The Carfax Vehicle History Report is the company's core product. Users purchase either a single report or create an account for building multiple reports for different vehicles, allowing consumers to utilize Carfax over a period of time as they search for a vehicle. Additionally, buyers can request Carfax reports for free from auto dealers who offer Carfax service, and some automakers routinely provide Carfax reports as part of their pre-owned vehicle programs.