What is a Single Elimination Bracket?
Also known as a knockout or sudden death bracket in sports, a single-elimination bracket does it’s best to match up the highest-ranked participating teams into the first round of games with play in games to those teams leftover. In a single elimination bracket, there can be several rounds of games, and the matches are played until there’s there’s one undefeated champion.
In a single elimination bracket, the number of rounds are determined by the number of teams in the tournament. The more teams there are, the more rounds there are. The range of rounds varies. On the low end, there is a minimum of two rounds with a bracket featuring four teams or individuals, or as high as seven rounds when there’s 128 participants. Usually a tournament will fall in between that range.
How to Refer to Each Round
|Participants||Round of||Officially||By Rounds|
|2||Round of 2||Final||7th Round|
|4||Round of 4||Semifinals||6th Round|
|8||Round of 8||Quarterfinals||5th Round|
|16||Round of 16||Eighth-finals||4th Round|
|32||Round of 32||16th-finals||3rd Round|
|64||Round of 64||32nd-finals||2nd Round|
|128||Round of 128||64th-finals||1st Round|
The above shows you how to refer to each round with a 128 team bracket. If the bracket has fewer than 128 participants/teams, then the round with the most teams is the first round, and so on.
Sometimes tournaments will have specific names for those rounds. The most popular single elimination basketball tournament is the NCAA Men’s Basketball Tournament (otherwise known as “March Madness”) refers to the rounds after the Round of 32 as the “Sweet Sixteen” the “Elite Eight” and the “Final Four”. This nomenclature are a few of the many trademarks owned by the NCAA.
Number of Teams Determine Bracket Complexity
Once a field is finalized and properly seeded into the tournament bracket, then the game action can begin.
Depending on the amount of teams, the opening round can be an initial round of play-games where the top seeds receive a bye. From a management perspective, the ideal tournament wouldn’t have play-in games and every participating tourney team would have an opponent from the get-go.
For a better understanding of how the number of teams impact the flow of a single elimination tournament, we created this quick reference table comparing single elimination brackets. We look at each tournament bracket’s attributes (total rounds, play-in games, etc.) and how that changes depending on the amount of teams in that single-elimination tournament.
|# of Teams||Rounds||Play-In Games||Seeds w/ Byes||Download|
|4 teams||Two||None||None||4-team bracket|
|5 teams||Three||One||#1 seed||5-team bracket|
|6 teams||Three||Two||#1 & #2 seeds||6-team bracket|
|7 teams||Three||Three||#1 seed||7-team bracket|
|8 teams||Three||None||None||8-team bracket|
|9 teams||Four||One||#1-#7 seeds||9-team bracket|
|10 teams||Four||Two||#1-#6 seeds||10-team bracket|
|11 teams||Four||Three||#1-#5 seeds||11-team bracket|
|12 teams||Four||Four||#1-#4 seeds||12-team bracket|
|13 teams||Four||Five||#1-#3 seeds||13-team bracket|
|14 teams||Four||Six||#1 & #2 seeds||14-team bracket|
|15 teams||Four||Seven||#1 seed||15-team bracket|
|16 teams||Four||None||None||16-team bracket|
|17 teams||Five||One||#1 seed||17-team bracket|
|18 teams||Five||Two||#1 & #2 seeds||18-team bracket|
|19 teams||Five||Three||#1-#3 seeds||19-team bracket|
|20 teams||Five||Four||#1-#4 seeds||20-team bracket|
|21 teams||Five||Five||#1-#5 seeds||21-team bracket|
|22 teams||Five||Six||#1-#6 seeds||22-team bracket|
|23 teams||Five||Seven||#1-#7 seeds||23-team bracket|
|24 teams||Five||Eight||#1-#8 seeds||24-team bracket|
|25 teams||Five||Nine||#1-#7 seeds||25-team bracket|
|30 teams||Five||Fourteen||#1 & #2 seeds||30-team bracket|
|32 teams||Five||None||None||32-team bracket|
|64 teams||Six||None||None||64-team bracket|
|128 teams||Seven||None||None||128-team bracket|
As you can from the above table, how many teams a single-elimination tournament has can simplify or complicate a bracket. If one team drops out, it can have a positive or negative affect on the flow of the tournament. It’s no coincidence that the brackets with 4, 8, 16, 32, and 64 teams don’t have play-in games or any byes whereas any other amount of teams between 4-64 will have at least one play-in game and one bye.
Does a single elimination bracket not satisfy your tournament needs? There are several different tournament bracket layouts and formats like double-elimination brackets to consider. All depend on personal preference, the sport being played, tournament timing and other factors.