Pharrell Williams' crazy hat steals the show at Grammy Awards 2014

The 'Happy' singer stepped out in an over-sized Fedora on Sunday night

Pharrell Williams' hat stole the show at the 56th Grammy Awards in Los Angeles (Getty Images)

He may have won a handful of Grammys on Sunday night, but it was Pharrell Williams’ bizarre choice of headgear that really stole the show.

The US music producer, 40, ignored the formal dress code to team an over-sized hat - a Fedora, apparently – with a red and white bomber jacket and jeans.

But while it may look like a joke, Williams’ hat is designer - Vivienne Westwood 1980s vintage no less.

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Grammys viewers could hardly care less, however, as Photoshop edits and Harry Potter comparisons have been flying on social media. One Twitter user even noted that the famous hat could resemble a "big toe".

Within minutes, the novel accessory had earned its own Twitter handle, @Pharrellhat, which to date has amassed over 14,500 followers.

Williams backed his fashion decision, tweeting with confidence that he is "def more fashionable than Madonna’s grill", referring to the singer’s strange mouthwear for the ceremony.

 The "Get Lucky" star debuted his hat in an edgy Instagram post involving a bike trick last week.

Pharell debuted his hat in this Instagram post last week (Pharrell Williams)

Williams ended 2013 at number one in the UK Official Singles Chart with "Happy", which features in 3D animated comedy Despicable Me 2 .

The track's music video is a 24-hour interactive film following a cast of hundreds as they dance through the streets of Los Angeles.

Williams won Producer of the Year, Record of the Year and Pop/Duo Group Performance at the 56th annual Grammy Awards. Other big winners included Ryan Lewis & Macklemore, Daft Punk, Lorde, Kacey Musgraves and Justin Timberlake.

Next month, Williams will perform live at the BRIT Awards in London, alongside Arctic Monkeys, Katy Perry and Bruno Mars.