It depends on how many a side it is.
Most of the time it is 15 on each team so 30 altogether.
12
Each team has 15 players, so there would be 30 players in total at the start of the match.
15
There can be 11 players per team on the football field
If you mean football as in soccer, then there are 11 players on the field for each team. In total there are 22 players.
At a start of a match there are 31 people on the pitch. Two teams of 15 players each and the referee.
11 players
11
12 players can be on the field at one time.
There are 11 players per team on the field at once. 22 players total. 1 football.
I was watching Mexican football, and the winning team had 12 players on the field.
There are 11 football players on each team and there is to teams. So all together there are 22 football players on the field and 4 referees.