The 90210 actress, who is the daughter of Demi Moore and Bruce Willis, showed off her new look at the Just Jared Annual Summer Party at Pink Taco in West Hollywood on Saturday (12 July).
Rumer joined the likes of Bella Thorne, Ashley Greene and Shenae Grimes at Saturday's swanky do, where she hit the decks to show off her DJing skills.
And while we weren't 100% sure of her outfit (well, mainly the gladiator heels!), her hair looked absolutely stunning.
The brightly coloured long locks had been totally chopped off and replaced with what can only be described as a super-sophisticated bob her mum and hair icon, Demi would be totally proud of!
And with other Hollywood A-listers like Hayden Panettiere, Vanessa Hudgens and Ashley Tisdale also going for blonde bobs recently, it seems there's never a better time to lighten up and go for the chop.
Rumer had already given us a cheeky glimpse of her sharp, angled new cut on Instagram at the weekend, when she posted a stunning profile shot of her swingy new do.
Her cut was created by Dominick Serna at the Chris McMillan Salon and coloured by Amber Maynard at Nine Zero One in West Hollywood.
And what a grand job they did. Makes us want to whip off our lengths and go platinum blonde right now!
At the same time, however, we're also loving the rainbow coloured locks some of our favourite celebrities are rocking this summer.
With Rita Ora doing dip-dye, MIC's Ashley James going lilac and Nicole Richie working her locks into a new blue shade, the colouring options really are endless.
And in the meantime, it's a big tick for Rumer because we much prefer her as a chic, sophisticated blonde. What thinks you?
Do you prefer Rumer with long, hot pink hair or with her new blonde bob? Let us know below. Our fave comment across the site each week wins £50!
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