The 'Dark Horse' singer took a snap of her a-mazing new barnet before sharing it with her Instagram fans earlier this week (8 December).
During her last red carpet appearance in November, Katy sported her trademark jet black hair colour with the lengths piled up high on the top of her head.
But it seems she got a little bit bored of that shade, dying her mane a very vibrant violet hue while chopping it into a shoulder-grazing bob.
How awesome does she look?!
Of course it's not the first time K-Pez has experimented with her hair colour. Back in April Katy dyed her tresses a "slime green" hue for spring, and she's also previously rocked eye-popping blue and pink looks (and suited all of them... jealous!).
To go with her new purple shade, the songstress wore a printed raincoat teamed with an adorable matching dress, defining her bold blue eyes with babydoll false lashes while slicking on a wintery mauve lipstick.
Commenting on her quirky outfit, Katy captioned her photo: "OOTD school girl raincoat vibez."
What do you think of Katy's purple hair? Let us know by commenting below as the best comment across the site each week wins £50!
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