Guide
How Many Games Are in a Round Robin Tournament?
Use the round-robin game formula to calculate how many games are needed for any number of teams.
How Many Games Are in a Round Robin Tournament?
The number of games in a single round-robin tournament depends on the number of teams. Each team plays every other team once.
Formula
Games = teams × (teams - 1) ÷ 2
This works because every team has to play every other team, but each matchup should only be counted once.
Examples
| Teams | Calculation | Games |
|---|---|---|
| 3 | 3 × 2 ÷ 2 | 3 |
| 4 | 4 × 3 ÷ 2 | 6 |
| 5 | 5 × 4 ÷ 2 | 10 |
| 6 | 6 × 5 ÷ 2 | 15 |
| 8 | 8 × 7 ÷ 2 | 28 |
| 10 | 10 × 9 ÷ 2 | 45 |
| 12 | 12 × 11 ÷ 2 | 66 |
Double round robin
For a double round robin, multiply the single round-robin total by 2.
Example: 6 teams need 15 games for a single round robin and 30 games for a double round robin.
Why the number grows quickly
Adding one team adds a game against every existing team. That is why round robin is excellent for small groups but becomes difficult with larger events.
Planning tip
After calculating total games, divide by available courts or fields. Then multiply by game slot length to estimate total event time.