Fox, 54, broke down in tears as the verdicts were delivered at Westminster Magistrates’ Court.
Reading the verdicts during a four-minute hearing, chief magistrate Howard Riddle said the victims were believable but that the bench “could not be sure that in the context it was a criminal offence”.
The former Capital FM host and ex-Pop Idol judge faced a string of indecent assault and sexual assault charges in relation to alleged offences that dated back to the 1980s, against women and girls as young as 14.
Fox has been suspended from Magic FM following his arrest, five minutes after he came off air in September last year.
His wife Vicky, who sat with her eyes closed before the verdicts were returned, celebrated silently with her husband’s supporters in the public gallery following the conclusion of the case.
Fox choked back tears as he spoke of his relief at his acquittal outside court.
He said: “This case has, once again, exposed concerns about how high-profile cases are investigated by the police and the CPS.”