Jessie J has dyed her hair blonde.

The 'Price Tag' singer - famed for her shoulder length black bob hairdo - shaved her locks off for charity Comic Relief on March 15 and celebrated her 25th birthday today (27.03.13) by dyeing her stubble.

Under a picture of her new look, she wrote on Instagram: ''It's my birthday and I'll be blonde if I want to.''

Jessie is currently away with friends to celebrate her birthday, but sent a message of thanks to all those who have wished her well.

She wrote on Twitter: ''I have no signal where I am so I'm hoping this sends!! Thank you in advance for all the birthday tweets and messages!!! I feel so happy right now!!! I'm 25!!! Waahhh!!! #birthdaymadness (sic).''

Jessie raised over £500,000 in sponsorship fees for Comic Relief by cutting off her hair, and says she chose to do something so extreme because it is a statement which will last.

After her hair had been shaved off, Jessie said: ''It's the weirdest feeling. My mum's crying with happiness.''

She later added on Twitter: ''I am soooo thankful to everyone who has donated @rednoseday and supported me tonight! My heart is filled with happiness! Lets make a change! X (sic).''