Swiss tournament generator that pairs every round for you

Round one is the only round that can be drawn in advance. The generator sorts your list by seed, splits it down the middle, and plays the top half against the bottom half — seed 1 against seed 9 in a field of 16. That is the standard slide, and it is why the order you paste your teams in matters.

Every round after that is paired from the results, not from the seedings. The generator ranks the field by points, then solves the whole round at once as a minimum-weight matching: rematches carry a penalty large enough that one is only ever chosen when no rematch-free pairing exists at all, then teams on equal points are kept together, then closer seeds are preferred. Pairing the leader greedily with their nearest valid opponent is easier to do by hand and reliably produces a worse round further down the table — which is the actual reason Swiss is painful on paper.

That is also why the widget above will not show you round two until every round-one match has a score. It is not a paywall or a loading state: in Swiss the next draw does not exist until the current results do. If you want the pairing rules themselves rather than a tool that applies them, how the Swiss system works covers them in detail.

Swiss match counts grow linearly, which is the whole point: rounds are ⌈log₂ n⌉ and each round is ⌊n ÷ 2⌋ matches, so doubling the field roughly doubles the matches instead of quadrupling them. Sixty-four players is 192 matches over six rounds; a round robin at the same size is 2,016.

The scheduling shape is different from a bracket, too. Every match in a Swiss round starts together and the round is only over when the slowest one finishes, so your day is round count × round length, not a widening-then-narrowing bracket. Sixteen players is eight matches a round: on four courts at 25-minute slots that is two slots per round and eight slots overall, about three hours twenty. The same sixteen as a straight knockout is five slots, roughly two hours — so four guaranteed games instead of one costs you about an hour and a quarter.

Where that trade stops working is when your entrants play at wildly different speeds and you have no clock. A slow board holds up an entire round, which is why chess Swiss events run a fixed time control and why chess organizers can promise a finish time that a knockout organizer cannot.

The generator scores 3-1-0 and treats a bye as a win, exactly as Tournamyx Scores does. Ties are broken on Buchholz — the sum of your opponents’ points — because in a format where everyone plays the same number of games, the only thing separating two teams on equal points is who they had to beat to get there. A bye counts as a virtual opponent scoring what you scored, so sitting out a round no longer quietly wrecks your tiebreak. Below Buchholz the order is head-to-head, then wins, then seed.

Publish that order before round one. Swiss finishes with teams level on points far more often than not — that is a property of the format, not a failure of it — and a tiebreak rule announced after the standings appear is the one thing that will get argued about at prize-giving.

The other property to plan around is that Swiss has no showpiece final. The last round is several simultaneous matches and the winner is whoever tops the table, which suits chess and esports but disappoints a crowd that came to watch a final. The usual fix is a Swiss stage that seeds a short knockout — the same shape as a group stage feeding a bracket, and how most esports majors are run. Tournamyx Scores chains the stages so the top finishers drop into the bracket automatically.