When organizing a tournament, it's helpful to get an early sense of how the number of teams affects how many fields you'll need. At Cup Manager, we regularly help tournaments work out how many teams they can accept, or whether they should try to secure more fields.

Here we want to share a few tips on how to think about capacity planning for your tournament.

Further down, we've also built a calculator to help you crunch the numbers for your own tournament.

Assuming all your groups are the same size, you know that every team plays each of the other teams in the group once. As you can see in the picture below, every team plays 3 games in a group of 4 teams.

4 teams each playing 3 games? It's tempting to think the total number of games must be 3 × 4 = 12 games. But that's not quite right. Look again at the number of lines/arcs in the picture above. 12 is the number of times a team appears in a game, but since there are two teams in every game, the actual number of games is half that, i.e. 6 games.

So a group of four teams produces 6 games:

More generally, the total number of games can be expressed as:

And you can use the same formula for a whole tournament. For example, if you're planning to have 200 teams in your tournament and everyone plays 3 games (as with groups of 4 teams), that comes out to 300 games.

Feel free to plug in your own numbers.

To work out how many games are in a playoff bracket, start with one key insight: in a knockout bracket, exactly one team is eliminated in every game, and at the end there's one team left as the winner of the final. So the number of games must equal the number of teams entering the playoffs, minus one. As an example, take a playoff bracket that starts with the quarter-finals. There, 8 teams enter and one team remains as the winner. Seven teams are eliminated, so there are seven games in the bracket.

This rule holds even if the bracket isn't “even” or balanced. If you also have a third-place match in your bracket, that's naturally one extra game, meaning the number of games equals the number of teams. If you have placement games for every team, it gets a bit more complicated.

Example: Say we have 6 age groups, each with an A and a B playoff bracket, giving us 12 brackets in total. If all 200 teams in our tournament advance to either the A or B bracket, the total number of playoff games works out to:

So in our example tournament, we end up with 300 group-stage games + 188 playoff games = 488 games in total.

To take the next step and calculate how much time you'll need, we need to know how long each game takes. A game has a duration, say 2×15 minutes, but there's also a break before the next game starts, say 2 minutes. That means games start 32 minutes apart.

By multiplying the interval between games by the total number of games, we can work out the total time needed for the tournament:

of which 160 hours are group stage and 100 hours are playoffs.

From this, we can work out how many fields you'll need depending on when you start in the morning and finish in the evening.

For example, if you're going to play the entire group stage from 08:00 to 20:00 in a single day, that means you have 12 hours per field. From there, it's easy to work out how many fields you need by dividing the total time required by the number of hours you have per field.

Rounded up, that's 14 fields.

You can do the same calculation for the playoffs.

Keep in mind, though, that this gives you the minimum number of fields, assuming every game can be packed in tightly with no gaps at all in the schedule. In practice, it's rarely possible to pack things at 100%, especially in the playoffs, where games depend on the results of earlier games.

Below, we've built an interactive tool that lets you run the numbers for your own tournament.

We hope this article and the calculator have helped you work out the capacity for your tournament.

At Cup Manager, we help tournaments large and small every day, both with calculations like these and with building fantastic match schedules. Feel free to get in touch to learn more and see a demonstration of what we can do for you.