full size Katy Perry Arrives at the 2013 Grammy Awards

Katy Perry's girls are so famously ample, they were spoofed on Saturday Night Live and even Ellen DeGeneres couldn't stop gawking at them.

Ellen got a good peek when Katy wore a revealing green dress to the 2013 Grammys. Apparently Katy’s Grammys look got people speculating that maybe she had augmented the goods. But RumorFix talked to a source close to Katy, who said, "No she didn’t have a boob job. It was that dress — it pushed her breasts out!”

A couple of years ago, Katy talked about wanting to reduce her breast size when she was 13. "I had really bad back problems and was a little bit thicker,” she said (via Showbiz Spy). “Then I grew up and lost the baby fat and said, ‘Hey, this isn’t all that bad.’ ”

Not bad at all. John Mayer probably agrees, too.

Sources: RumorFix, Showbiz Spy