The 100m breaststroke champion from Rio 2016 is targeting a title defence at Tokyo 2020, which would make him the first ever British swimmer to win consecutive Olympic gold medals.
Peaty, 22, is also the reigning Commonwealth and European champion, and set two world records en route to victory in Brazil last summer.
Peaty sets fastest time this year at Team GB swimming trials
And having already made history by winning in Rio, the thought of adding to his legacy is his new driving force for the next four years.
"I think I can defend my titles, but defending my Olympic title is my main motivation," he told BBC Sport.
"Before Rio it was no British man had won Olympic gold in 28 years. Now it is no British person in swimming has ever defended an Olympic title. It is definitely achievable, so why not?"
And it's not just titles that are spurring him on, with the prospect of lowering his world record even further a realistic possibility.
His first opportunity to do so will come at the British Swimming Championships in Sheffield, next month, with that event acting as the qualifier for July's World Championships, in Hungary.
"At Rio, 57.1 was very, very fast, but I went 56.5 in the relay so I am guessing that there is a little more in there," he added.
"Getting 56 would be outrageous because it would be two seconds and a bit above everyone else in the world, which is unheard of in swimming." Sportsbeat 2017
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