# How are the number of laps in an F1 race determined?

The number of laps in a F1 race seem to differ wildly. Obviously the length of each lap varies from circuit to circuit, but how are the number of laps for each race decided?

Additionally, is this number chosen by the owners of the race track, or something decided by the FIA/ teams?

The number of laps are decided by taking a distance of 305 km and dividing it by the length of a lap (rounded up), which varies from racetrack to racetrack. (1)

quoting the official regulations (from 2011):

5.3
The distance of all races, from the start signal referred to in Article 38.9 to the chequered flag, shall be equal to the least number of complete laps which exceed a distance of 305 km (Monaco 260km). However, should two hours elapse before the scheduled race distance is completed, the leader will be shown the chequered flag when he crosses the control line (the Line) at the end of the lap during which the two hour period ended. However, should the race be suspended (see Article 41) the length of the suspension will be added to this period.

• The mathematical formula is therefore 305 / lap length in km (rounded up). This also means that the longest races in terms of time are those where the average speed is slowest. Apr 8 '12 at 18:53
• I think this answer actually covers the how perfectly - simple mathematics. Why wasn't asked, but is probablt a combination of identifying a useful length to interest drivers, advertisers, management etc. May 31 '12 at 8:02
• original answer contains no original content
– user527
Oct 31 '12 at 16:04