According to FIFA regulations, a football match lasts for two equal periods of 45 minutes, for a total time of 90 minutes. Any alteration to this must be made prior to the game and agreed upon by both teams and the match official.
The time of a football match is 90 minutes, although it's customary for the match official to add time on to the end of each half if there were prolonged stoppages or delays during the run of play. In tournament situations where a winner must be declared, if a match is tied after 90 minutes, there will be two extra periods of 15 minutes each played. If the score remains tied, a penalty shootout will decide the winner.