TrueCar, Inc. is an automotive pricing and information website for new and used car buyers and dealers. TrueCar is paid by dealerships so they can obtain potential buyers' contact information. Potential car buyers receive an online report illustrating what others have paid for cars, illustrative pricing from a network of TrueCar Certified Dealers. TrueCar reports its users have purchased more than 2 million cars from dealers in its network. The company is headquartered in Santa Monica, California, and its network includes around 10,000 automobile dealers in the United States.

TrueCar's "massive up-to-the-minute database of selling prices" is an example of big data at the petabyte level and is run on Apache Hadoop.

TrueCar was originally incorporated under the name "Zag.com Inc." in Delaware in February 2005. Scott Painter, along with several co-founders, including Tom Taira and Jim Nguyen operated the business primarily as a provider of “white-labeled” auto-buying programs for affinity groups. Within the Zag.com environment, the concepts of price confidence using data and analytics presented in an easy-to-digest form was incubated and launched in a separate company, TrueCar.com. The TrueCar concept involved gathering data from a number of different sources in order to compile updated vehicle prices for consumers in an attempt to enhance Zag.com's services. Ultimately, the two entities were combined to form TrueCar, Inc.

TrueCar ranked 11th on the L.A. Business (LAB) annual list of the 100 Fastest Growing Private Companies in Los Angeles, and Inc. Magazine ranked TrueCar on its 2010 list of Fastest Growing Companies in America.

In January 2011, TrueCar released ClearBook.com, a used vehicle index that analyzes the used car market. The website provides users with prices based on market data.

In August 2011, TrueCar raised $200 million in debt and equity financing, and purchased ALG, a company that provides information on future residual values of vehicles, for an estimated $83 million. TrueCar later hired Larry Dominique, former vice president of product planning at Nissan, to run its ALG business and work with auto manufacturers. Additional 2011 deals included the acquisition of News Corp-backed Honk.com in May.

In late 2011, TrueCar launched a television advertising campaign with commercials promoting its services. Shortly thereafter, TrueCar faced backlash from the automotive industry, when several state agencies and regulators notified TrueCar that its practices were noncompliant with some state laws. In response to those notices, TrueCar overhauled its pricing structure, and moved from a pay-per-sale model to a subscription model for dealers in some states.

In 2013, about 400,000 vehicles were sold from TrueCar and TrueCar Certified Dealers. In 2014, more than 611,000 new and used vehicles were purchased at TrueCar Certified Dealerships. TrueCar had a hand in 3.9% of U.S. new car retail sales in 2014. As of October 2015, TrueCar had more than 10,000 dealerships in its network.

In February 2014, TrueCar acquired the domain True.com, using the site as an umbrella domain name. On May 16, 2014, TrueCar became a publicly traded company and is listed on the NASDAQ under the ticker, NASDAQ: TRUE. TrueCar successfully completed a secondary offering in November 2014 worth approximately $125 million.

Painter stepped down as CEO of TrueCar in December 2015. He was replaced by Chip Perry.

In its 2008 Series A round of venture funding, TrueCar raised $2.8 million from Zag's original investors. It received $8.1 million in Series B investments from Capital One and Anthem Venture Partners and TrueCar raised another $35.5 million in 2010.

In September 2011, TrueCar raised $200 million in funding from USAA, GRP Partners, Keating Capital, Silicon Valley Bank and Capricorn Investment Group.

Truecar raised $30 million from Vulcan Capital in December 2013. As of 2013, the company has raised over $200 million in financing since its founding in 2005.

TrueCar launched the first all-female racing team in 2012, with support from Penske Media Corporation and Dragon Racing. The companies sponsored the women in six racing series, including IndyCar, Global MX-5 Cup, Star Mazda, USF2000, World Challenge and Rally America. In June 2012, The Virgin Group announced its partnership in support of TrueCar's "Women Empowered" initiative.

TrueCar powers car-buying programs for approximately 576 brands. TrueCar’s Affinity Partners include USAA, Sam's Club, Consumer Reports, AAA, American Express, Geico and Farmers.