Zagat Survey ( /zəˈɡæt/) was established by Tim and Nina Zagat in 1979 as a way to collect and correlate the ratings of restaurants by diners. For their first guide, covering New York City, the Zagats surveyed their friends. As of 2005, the Zagat Survey included 70 cities, with reviews based on the input of 250,000 individuals reporting over the years. In addition to restaurants, Zagat guides rate hotels, nightlife, shopping, zoos, music, movies, theaters, golf courses and airlines. The guides are sold in book form, and formally as a paid subscription on its web site.

As of May 2012, as part of its acquisition by Google in September 2011, Zagat reviews and ratings became tightly integrated into Google's services, and the Zagat.com site became free to use.

The ratings are on a 30-point scale, made up of ratings for defined areas including food, decor, service, and cost. In addition to numeric scores, the survey also includes a short descriptive paragraph that incorporates selected quotations (typically a few words) from several reviewers' comments about each restaurant or service, as well as typical pricing and other information.