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Check out Katy's different looks over the years.
Katy Perry's latest look is this hot pink hair which she showed off at the MTV VMAs.
Katy recently had a two-tone blonde and caramel do.
The singer shows off hot ginger curls while promoting her perfume.
Keeping it chic, Katy wears sleek black waves.
At a French fashion show earlier this year, it's a blue barnet for Katy.
Another blue wig completely transforms the 'E.T.' singer at the 2010 MTV Movie Awards.
Last year Katy added a rainbow of highlights to her brunette bonce.
Is it a bun? Is it a ponytail? Katy manages to pull off two styles at once.
Katy channels the 1940s with neat dark waves.
Did Jessie J model her blunt black bob on Katy's 2009 look?
Katy sports a lady-like up do at a bash earlier that year.
It's big hair for Katy at the 2008 MTV Europe Music Awards.
Early on it's vintage style for Katy Perry in a frilly frock and tight brunette curls.
At the start of her career in 2008 Katy sported a fringe and shaggy rock chick locks.
Honey-coloured highlights were Katy Perry's 'Teenage Dream'. Pic: WENN