Roger Federer spent 237 consecutive weeks as the world No. 1 in men's singles. He held the top ranking from 2 February 2004 until 17 August 2008, establishing one of the most enduring records in tennis history.
Federer finished those years as the dominant player of his generation, winning three Australian Open titles, five straight Wimbledon titles, and four consecutive US Open titles during that broader period. His consistency was especially remarkable because the ATP ranking is calculated from tournament results rather than a single championship.
The number 237 is often confused with Federer's total of 310 weeks at No. 1. The latter counts all of his separate reigns, including a return to the top in 2018. Novak Djokovic later surpassed Federer's overall total, but Federer's 237-week uninterrupted run remains a distinct consecutive-weeks record.