How to Work Out a Tournament Bracket

Matches always equal entrants minus one

Every match eliminates exactly one competitor. To find a winner you must eliminate everyone else. So:

N entrants → N − 1 matches. Exactly, not approximately.

Twenty-four entrants is always twenty-three matches, regardless of bracket size, byes, seeding or how the draw falls. A third-place match adds exactly one more.

That single fact budgets an entire event before a bracket is drawn or you know who turned up.

Why the bracket is a power of two

Every round halves the field, and that only works cleanly from a power of two: 16 → 8 → 4 → 2 → winner.

Start with 24 and the first round can't halve evenly, so you draw a 32 bracket and the eight unfilled slots become byes — free passes through round one. After that the field is a clean sixteen and every subsequent round halves properly.

This is why entry counts just above a power of two produce so many byes:

Entrants	Bracket	Byes	First-round matches
16	16	0	8
17	32	15	1
24	32	8	8
32	32	0	16

Seventeen entrants means a single first-round match while fifteen people watch. Worth knowing before you close entries — one more or seven fewer changes the shape of the morning completely.

Who gets the byes

By convention, the top seeds. That's a fairness decision rather than an arithmetic one.

Giving byes to the strongest entrants protects them from an early upset and is standard in seeded events. Distributing them randomly is more even-handed and less predictable.

Either is defensible. What matters is deciding and announcing it before the draw — settling it afterwards always looks like it was settled to suit somebody.

The time figure is a floor

Shortest the event could run assumes every station runs continuously and each round starts the instant enough matches finish. Neither survives contact with a real event.

Rounds can't overlap — the next one can't begin until its participants are known, so a round takes as long as its slowest match rather than its average. Late arrivals, disputes, equipment failures and breaks all add more.

And the tail is unavoidably serial. A final is one match on one station however many you have. Parallelism stops helping precisely when you're most behind schedule, which is why the last hour of an overrunning tournament can't be recovered by opening more tables.

Build in more slack than feels necessary. The cost is asymmetric: finishing early is pleasant, finishing late loses your venue.

One easy improvement — put changeover time inside your match length. The gap between matches is real, and it happens as many times as there are matches.

Reading the first-round number

Matches in the first round is the one to look at when planning the morning, because it's the only round whose size isn't simply half the last.

It's your entrant count minus half the bracket. At 24 that's 8 matches while 16 players wait; at 17 it's a single match while 15 wait. After that round the field is always a clean power of two and every subsequent round is exactly half the one before — 8, 4, 2, 1.

That shape matters for scheduling people rather than matches. A round with many byes means a lot of entrants arriving for a start time they don't actually play at, which is worth communicating rather than leaving them to discover it. Some organisers stagger arrival times for exactly this reason; others run the first round late enough that everyone is present anyway.

The other formats, briefly

Double elimination roughly doubles the match count, because almost everyone must be beaten twice. Fairer, since one bad match no longer ends someone's day, and it needs about twice the schedule for the same field.

Round-robin is everyone against everyone: N × (N−1) ÷ 2 matches. It grows with the square of the field, so eight entrants is 28 matches and twenty-four is 276 — not a one-day event on four stations. It's the fairest format by some distance, since results don't depend on the draw, which is why it's common in small groups and as a group stage feeding a knockout bracket.