Organization and Business Description	9 Months Ended
Sep. 30, 2021
Accounting Policies [Abstract]
Organization and Business Description	1. Organization and Business Description CarGurus, Inc. (the “Company”) is a multinational, online automotive platform for buying and selling vehicles that is building upon its industry-leading listings marketplace with both digital retail solutions and the CarOffer online wholesale platform. The CarGurus marketplace gives consumers the confidence to purchase or sell a vehicle either online or in-person; and gives dealerships the power to accurately price, effectively market, instantly acquire and quickly sell vehicles, all with a nationwide reach. The Company uses proprietary technology, search algorithms and data analytics to bring trust, transparency and competitive pricing to the automotive shopping experience. The Company is headquartered in Cambridge, Massachusetts and was incorporated in the State of Delaware on June 26, 2015. The Company operates principally in the United States. In the United States, it also operates as independent brands the Autolist online marketplace, which it wholly owns, and the CarOffer, LLC (“CarOffer”) digital wholesale marketplace, in which it has a 51% interest. In addition to the United States, the Company operates online marketplaces under the CarGurus brand in Canada and the United Kingdom. In the United Kingdom, it also operates as an independent brand the PistonHeads online marketplace, which it wholly owns. The Company also operated online marketplaces in Germany, Italy, and Spain until it ceased the operations of each of these marketplaces in the second quarter of 2020. The Company has subsidiaries in the United States, Canada, Ireland, and the United Kingdom. Additionally, it has two reportable segments, United States and International. See Note 13 of the Unaudited Condensed Consolidated Financial Statements included elsewhere in this Quarterly Report.

Organization and Business Description

9 Months Ended

Sep. 30, 2021

1. Organization and Business Description

CarGurus, Inc. (the “Company”) is a multinational, online automotive platform for buying and selling vehicles that is building upon its industry-leading listings marketplace with both digital retail solutions and the CarOffer online wholesale platform. The CarGurus marketplace gives consumers the confidence to purchase or sell a vehicle either online or in-person; and gives dealerships the power to accurately price, effectively market, instantly acquire and quickly sell vehicles, all with a nationwide reach. The Company uses proprietary technology, search algorithms and data analytics to bring trust, transparency and competitive pricing to the automotive shopping experience.

The Company is headquartered in Cambridge, Massachusetts and was incorporated in the State of Delaware on June 26, 2015.

The Company operates principally in the United States. In the United States, it also operates as independent brands the Autolist online marketplace, which it wholly owns, and the CarOffer, LLC (“CarOffer”) digital wholesale marketplace, in which it has a 51% interest. In addition to the United States, the Company operates online marketplaces under the CarGurus brand in Canada and the United Kingdom. In the United Kingdom, it also operates as an independent brand the PistonHeads online marketplace, which it wholly owns. The Company also operated online marketplaces in Germany, Italy, and Spain until it ceased the operations of each of these marketplaces in the second quarter of 2020.

The Company has subsidiaries in the United States, Canada, Ireland, and the United Kingdom. Additionally, it has two reportable segments, United States and International. See Note 13 of the Unaudited Condensed Consolidated Financial Statements included elsewhere in this Quarterly Report.