A standard Australian rules football match is played over four quarters.
At the highest level, each quarter is scheduled for 20 minutes of playing time, with additional time added for stoppages. The teams change ends after each quarter, which helps balance conditions such as wind, sunlight and ground advantage. A half-time interval separates the second and third quarters, while shorter breaks occur between the other quarters.
The four-quarter structure is used in the Australian Football League and in many other competitions. Junior, school and community leagues can use shorter quarters or modified timing, so not every match has exactly the same duration. The basic four-period format, however, is the standard reference for the code.
Australian football’s timing differs from sports that use a continuously running clock or fixed halves. The clock is stopped for certain events, and the time displayed during a quarter does not necessarily equal the total elapsed time. This is why official matches usually last considerably longer than 80 minutes.