Tournament Bracket Rounds Calculator
For a single-elimination bracket, find the number of rounds, total games and first-round byes from the number of teams.
How it works
Rounds = ⌈log₂(teams)⌉ · Total games = teams − 1 · Byes = 2^rounds − teams
A single-elimination bracket doubles its survivors each round, so the number of rounds is the base-2 logarithm of the field, rounded up. Because every team except the eventual champion is eliminated exactly once, the total number of games is always one fewer than the number of teams. When the field is not a power of two, the difference up to the next power of two becomes first-round byes.
Worked example
With 12 teams, rounds = ⌈log₂ 12⌉ = 4, and the next power of two is 16, so there are 16 − 12 = 4 byes. The tournament plays 12 − 1 = 11 games in all.
Frequently asked questions
Why is the number of games always teams minus one?
In single elimination each game eliminates exactly one team, and all but the champion must be eliminated. So a field of N teams needs N − 1 eliminations, hence N − 1 games.
What is a bye?
A bye advances a team to the next round without playing, used when the field is not a power of two so the bracket can round up to the nearest 2, 4, 8, 16 and so on.
Does this cover double elimination?
No — this is single elimination. A double-elimination bracket has a losers’ side and plays roughly twice as many games, about 2N − 1 or 2N − 2.
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This calculator is for educational purposes. Double-check important results before acting on them.