March Madness Bracket Maker with Win Probability, Live Scores and a Leaderboard

A March Madness bracket with the odds of every pick

MES March Madness is a free NCAA tournament bracket maker for the men’s and women’s tournaments. Pick a winner for every game, from the First Four to the national championship, and see the chance that each pick comes true, the chance that your whole bracket is perfect, how many upsets you picked and how “chalky” it is. During the tournament the real scores come in by themselves, games in progress show ESPN’s live win probability, your points and the most you can still score update, and you can post your bracket to the leaderboard.

Before Selection Sunday

The field of 68 is announced on Selection Sunday (expected Sunday, March 14, 2027). Until then the page plays the most recent tournament with its real bracket and results: fill in your picks without looking (leave “Show real results” off), then switch the results on to see how you would have done. When the new field is out the page switches to it by itself.

How the win probability is worked out

It is a simple model you can check by hand, not a secret rating:

• First round: the historical record of that seed pairing (men since 1985, women since 1994; approximate): a 1 seed beats a 16 seed about 98.8% of the time in the men’s tournament, a 5 beats a 12 about 64%, an 8 beats a 9 about 48%.
• Later rounds: each seed has a rating fitted to those records and to how seeds have done against each other in later rounds; the chance is the logistic of the difference, \( P(A) = \dfrac{1}{1 + e^{-(r_A - r_B)}} \). Gaps are stretched by 1.3 for the women’s tournament, where favourites win more often.
• Season record: both are nudged by each team’s win percentage against what is usual for its seed (3 × the difference, in the same log-odds units). “Seeds only” turns the nudge off.
• During the tournament: a finished game counts as 100% or 0%, a game in progress uses ESPN’s live win probability, and each team’s chance to win a later game adds up every way it can get there.

The chance of a perfect bracket is the product of the chances of your 63 picks (each one given the teams you sent into that game). Chalk compares that with a bracket of the same games where the favourite always wins: 100 means you always took the favourite, lower means bolder.

Scoring

ESPN gives 10 points for each right pick in the round of 64, then 20, 40, 80, 160 and 320 for the champion (1,920 is perfect). Doubling is 1, 2, 4, 8, 16, 32. Upset bonus is the ESPN points plus the winning team’s seed, so a right pick of a 12 seed is worth more than a right pick of a 5 seed. First Four games are not scored. “Max” is your points plus every pick whose team is still alive.

Questions

When does the leaderboard lock?

At the first tip-off of the round of 64. A bracket posted or changed after that goes to the Replay board, which is just for fun (the results of earlier games are already known), so the main board stays fair.

Where do the results come from?

From ESPN’s public scoreboard, refreshed about every 30 seconds while games are on. Past tournaments are saved copies of the same data.

Is anything about me stored?

Your brackets stay in this browser. Only if you post to the leaderboard are the name you chose and your picks stored, with a private key in your browser that lets you change or remove them.

Not affiliated with the NCAA or ESPN. Team logos are ESPN’s and are shown only to tell the teams apart. This is a game for fun, not betting advice.