A friend close to the singers told People magazine that Perry and Mayer have ended their brief romance, but remain on good terms.
"They'll end up as friends," the source explained. "They were honestly having fun. People made it out to be far more than it was."
Rumours of a romance between the pair emerged in July when Mayer and Perry were spotted spending time together in Los Angeles.
A second source who saw the couple together earlier in August said: "They almost acted like they've been a couple for a long time. It definitely didn't seem like a new relationship."
Perry divorced comedian Russell Brand earlier this year, and recently broke up with Florence + the Machine guitarist Robert Ackroyd.
Watch Katy Perry's music video for 'The One That Got Away' below: