The singer, who has been criticised for apparently miming during her X Factor appearance, is hoping to kick off her comeback with the new album.
 
Britney started her birthday morning with a performance on Good Morning America, where she was presented with a huge Circus-themed birthday cake.
 
The star's two children, Preston and Jayden, were cheering her on from the audience.
 
Britney will celebrate tonight with a party at a chic New York nightclub with her friends and family.
 
Last year, for her 26th birthday, Britney was said to have received £15,000 worth of fur coats, a £5,000 diamond ring and some designer shades - and that was just from the hotel she was staying at.
 
Throughout her career Britney has achieved eight number one singles, five platinum albums, 800 awards including a Grammy and has sold 83 million records worldwide.

--- MAKE SURE TO CAST YOUR VOTE IN OUR 2008 OK! CELEBRITY POLL ---