Answer
As of 30 August 2022, Carolina Marin has been the longest world No.1 in BWF history, having held the top spot for a total of 214 weeks. She first reached the No.1 spot on 3 November 2014 and has held it for a total of 10 separate periods. Her longest period at No.1 was from 26 October 2015 to 27 May 2017, a total of 71 weeks.