Michelle Williams inspired Katy Perry's dramatic haircut.

The 'Roar' hitmaker has taken to social media to document her new beauty make-over, which has seen her ditch her bob for an even shorter blonde pixie crop, and the star has revealed the 36-year-old actress strongly influenced her decision to cut her hair.

The 32-year-old singer shared a string of short videos on her Instagram Story, which remains on the photo-sharing site for 24 hours, showing the process of her beauty transformation and her style muse.

Alongside a picture of the 'Manchester By The Sea' star, she wrote: ''SHOUT OUT MW INSPO (sic).''

The powerhouse has claimed she has ''redefined beauty'' with her latest look.

Speaking in the clips, which show her tresses being hacked off, she said: ''Bye. Let's re-define beauty, right Chris?''

And when asked by the beauty expert, Chris McMillan, if she likes her hair, she said: ''Yes, so happy.''

Katy also panned to a dog in the footage, who wanders around the hair snippings, which are on the floor.

She said: ''Nugget you made a mess, you can't bring me back. I just want to be who I want to be. Don't shame me.''

However, Katy has hinted she has contemplated cutting her locks for a while, but she ''wasn't ready'' until now.

The star - who recently confirmed her split from former boyfriend Orlando Bloom earlier this week - shared a string of videos of her hair being styled on her photo-sharing page in which she said: ''What do you think Chris?''

To which he replied: ''I love it. Are you kidding? I've been wanting to do this since the day I met, you, do you remember?''

And Katy answered: ''I remember. I wasn't ready.''

Katy also captioned the clips: ''I WASNT READY TIL NOW

''cash me outside howbow dah S/O @mrchrismcmillan and @justinandersoncolor & @riderdyehair for that platinum status (sic).''