Round robin schedule generator.

How is a round robin schedule made?

The circle method fixes one team and rotates the others one place each round, pairing the team at the top of the circle with the one at the bottom. With n teams (n even) that gives n − 1 rounds of n/2 games, and every pair meets exactly once. When n is odd, a dummy team is added so the schedule is built for n + 1; whoever is paired with the dummy has a bye that round, giving n rounds of (n − 1)/2 games. FIDE's Berger tables use the same idea: with an odd number of players, the highest number counts as a bye.

Worked example. Five teams A to E: the generator adds a dummy, builds 5 rounds with 2 games each, and each team sits out exactly one round. Total games are 5 × 4 / 2 = 10. For a double round robin the games double to 20 and the number of rounds doubles to 10.

What it does not do. It does not balance home and away, venues, travel or team availability. If those matter, use the pairings as a starting point and swap whole rounds, not single games, so each team still plays once per round.