who won the most money on a gameshow
Ken Jennings is the highest-earning American game show contestant of all time, having accumulated a total of $5,223,414.
American game show winnings records
 Ken Jennings is the highest-earning American game show contestant of all time, having accumulated a total of $5,223,414. 
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American game show winnings records [SEP] Introduction
, the top three winners in American game show history all earned the majority of their winnings from the quiz show "Jeopardy!", which has aired since 1984 and has had no hard earnings limit since 2003. Ken Jennings is the highest-earning American game show contestant of all time, having accumulated a total of $5,223,414. He took the record back from Brad Rutter as the highest-earning contestant (a record Rutter had held since 2014) by virtue of his victory on January 14, 2020 in the "Jeopardy! The Greatest of All Time" tournament.