The number of matches does not depend on the number of teams alone, but on how you divide them. The same 12 teams can produce 18 or 66 matches.
If everyone in a group plays everyone once, the number of matches is n × (n − 1) ÷ 2. For a group of 4: 4 × 3 ÷ 2 = 6.
| Teams in the group | Matches | Per team |
|---|---|---|
| 3 | 3 | 2 |
| 4 | 6 | 3 |
| 5 | 10 | 4 |
| 6 | 15 | 5 |
| 8 | 28 | 7 |
| 10 | 45 | 9 |
| 12 | 66 | 11 |
If you split the field over several groups, you simply add the groups together.
| Teams | Split | Group matches | Per team |
|---|---|---|---|
| 8 | 2 groups of 4 | 12 | 3 |
| 8 | 1 group of 8 | 28 | 7 |
| 9 | 3 groups of 3 | 9 | 2 |
| 10 | 2 groups of 5 | 20 | 4 |
| 12 | 4 groups of 3 | 12 | 2 |
| 12 | 3 groups of 4 | 18 | 3 |
| 12 | 2 groups of 6 | 30 | 5 |
| 16 | 4 groups of 4 | 24 | 3 |
A knockout with k teams costs k − 1 matches, plus 1 if you play a third-place play-off. Four teams in the final stage is therefore 3 matches, or 4 with the play-off. Eight teams: 7, or 8.
With placement matches it works differently: every group position keeps playing, so roughly as many matches are added as there are teams divided by two.
In the usual set-up of 3 groups of 4: 18 group matches. Play a final stage with 4 teams including a third-place play-off afterwards and you reach 22 matches, with every team playing at least 3.
Put at least 4 teams in a group. In a group of 4 everyone plays 3 matches; in a group of 3 only 2. For more certainty, choose placement matches: then everyone keeps playing after the groups too.
Usually because the change-over time was not counted. Per match, add the playing time and the time to switch pitches, and only then divide by the number of pitches.