John Mayer: I promise I'm normal

John Mayer has joked he gets checked for "normalcy".

The singer has captivated fans around the world with songs such as Who You Love and his cover of Tom Petty's Free Fallin'.

He's shared a throwback video of himself on Instagram, in which he wears a vest and tracksuit bottoms as she strums an acoustic guitar.

"#videotbt #tbt 2001. Way before iPhones, and probably due to dead batteries in a micro recorder, I put this idea down on my video camera so I wouldn't forget it. "If you let me leave/I swear I never will" was the line I was hot on," he shared with his followers.

"Looking back on it, it was the perfect summation of how I saw everything in my life in the beginning stages of commitment to a calling that would direct me away from "normalcy." (I get it checked every week now. I'm normal.)"

The 36-year-old is now one of the biggest artists on the planet and recently recorded a track with his now ex-girlfriend Katy Perry.

Despite his high-profile relationship with the Roar singer, John prefers to keep his feet on the ground and not succumb to the Hollywood lifestyle.

He does however occasionally check in on the positive feedback he's getting from his fans.

"Don't normally check mentions (mind is a sacred and safe place) but got masochistic and checked. Gotta say... You guys are really kind! (sic)" he thanked his followers on Twitter.