If every game were a coin flip, the odds of a perfect March Madness bracket would be 1 in 9,223,372,036,854,775,808. That is 2 multiplied by itself 63 times, once for each game in the bracket.
Knowing the teams improves that number by a huge factor and still leaves it out of reach. NCAA.com puts an average picker at about 1 in 120.2 billion, and in its tracking no bracket has ever been verified as perfect.
Which games a bracket counts
The 2027 men’s tournament is the first with 76 teams, up from 68. According to NCAA.com’s explainer, 24 of them play 12 opening-round games, and the 12 winners join the rest in a 64-team, single-elimination bracket.
A single-elimination bracket of 64 teams has 63 games, because every game knocks out one team and 63 have to go. That is the number the bracket math uses. When the opening round had four games, NCAA.com wrote that virtually all bracket pools left them out and started at the first round.
A contest that also scored the 12 opening-round games would ask for 75 picks. The coin-flip odds would then be 1 in 37,778,931,862,957,161,709,568, which is 4,096 times longer. Check your own contest’s rules for which games count.
What are the odds of a perfect March Madness bracket, round by round?
The chance of staying perfect falls with every game, so the odds multiply round by round. The middle column treats each game as a coin flip. The right-hand column uses NCAA.com’s estimate, drawn from picks in its Bracket Challenge Game, that an average player gets 66.7% of games right, applied to every game.
| Perfect through | Games | Coin flip: 1 in | Average picker: 1 in |
|---|---|---|---|
| First round | 32 | 4,294,967,296 | 424,593 |
| Second round | 48 | 281,474,976,710,656 | 276,668,663 |
| Sweet 16 | 56 | 72,057,594,037,927,936 | 7,062,416,086 |
| Elite Eight | 60 | 1,152,921,504,606,846,976 | 35,682,063,767 |
| Final Four | 62 | 4,611,686,018,427,387,904 | 80,204,419,006 |
| Championship | 63 | 9,223,372,036,854,775,808 | 120,246,505,256 |
Each coin-flip row is 2 raised to the number of games. Each average-picker row is 1 divided by 0.667 raised to the same number. The last row, rounded, is NCAA.com’s 1 in 120.2 billion, about 77 million times better than the coin flip.
Better picking moves the number a long way, but the exponent wins. A hypothetical picker right on 80% of games, every game, would still face 1 in 1,274,474 for all 63.
The longest verified perfect bracket
NCAA.com’s record is 49 games. Gregg Nigl, a neuropsychologist from Columbus, Ohio, picked the first 49 games of the 2019 tournament correctly in the Capital One NCAA March Madness Bracket Challenge, and his bracket busted on game 50, when Purdue beat Tennessee 99-94 in overtime in the Sweet 16. NCAA.com’s list of the longest streaks since 2014 shows how rare that is: the last perfect bracket busted on the 44th game in 2026 and on the 43rd in 2025.
Even 49 is a long shot by the same arithmetic. At 66.7% a game, 49 straight correct picks is about 1 in 414,795,597. Nigl still had 14 games left to pick.
What the number means for a bracket pool
Nobody wins a pool by being perfect. NCAA.com reports that winners of its Bracket Challenge Game have averaged around 50 correct games, and its odds explainer puts the share of unique brackets in that game at around 94%.
So the useful question is not how to be perfect but how to finish ahead of the other brackets in your pool. Our March Madness guide covers the 76-team format and the dates. Our bracket betting guide covers how bracket contests are run, and the Calcutta guide explains the pool where teams are auctioned instead of picked.