They've done it once and they did it again. After dating since last year, Katy Perry and John Mayer have broken up again.

According to reports from People magazine, Katy and John have called it quits. A source told the magazine that both artists have been busy and that Katy's windows are still open. For reconciliation or for another man maybe?

John Mayer was Katy's first ever serious relationship after her divorce with ex-husband Russell Brand. However, their relationship has always been private. They were frequently spotted together for dinner or emerging from hotels, but none of them have spoken publicly about each other or their relationship.

"It's sad. It's not over until it's over. You have to see how things play out," another source told US Weekly.

Katy and John were first spotted together in June of last year, they reportedly split around August. But the "break" was short lived since they were seen smooching at awards shows and restaurants the following month.

Just last month, the pair looked loved up while they attended the Grammy Awards. Katy even mentioned that her "boyfriend" introduced her to the smooth music of "Miguel."

For John Mayer however, he has quite a reputation for being a ladies man. He had several high-profile celebrities as girlfriends including Jessica Simpson, Taylor Swift and Jennifer Aniston. There was even a small feud between Taylor and John when the country singer hinted that her "Dear John" song was aimed at Mayer.

Perry was married to Brand for 14 months before the two divorced in 2011. Katy considered the event as "heartbreaking" and since then she has avoided being tangled in relationships. Katy was seen on causal dates in the past but none of them got to a semi serious stage like what she shared with John Mayer.

Also read:

Blake Shelton Cheated on Miranda Lambert?

Lindsey Vonn: Things You Need to Know About Tiger Woods' New Girlfriend [PHOTOS]