Jonathan Romesh Ranganathan (born 27 March 1978) is a British actor, comedian, and presenter with a Sri Lankan background. His style of comedy is deadpan and often self-deprecating.

Ranganathan has made numerous appearances on television comedy panel shows and has been a regular panellist on The Apprentice: You're Fired!, Play to the Whistle, and The Museum of Curiosity. He completed his first major tour, Irrational Live, in 2016; he performed in large venues such as the Hammersmith Apollo. In 2018, he joined A League of Their Own as a regular panellist. He has presented comedy programmes Judge Romesh and The Ranganation, as well as starring in the travel programme The Misadventures of Romesh Ranganathan. His autobiography, Straight Outta Crawley, was released in 2018. He began hosting the revival of The Weakest Link in 2021.

In 2020, Ranganathan won the BAFTA TV Award for Best Features for The Misadventures of Romesh Ranganathan. In 2021, he won the BAFTA TV Award for Best Entertainment Performance for The Ranganation.