NFL · win probability
NFL win probability from the spread, the score and the clock
A 3-point favorite wins 61% of NFL games, a 7-point favorite 75% and a 14-point favorite 91%. Enter the line, the score and the time left to see the chance of winning at any point of a game.
Point spread to win probability, before kickoff
The favorite’s chance of winning at each closing line, from the model fitted on 1,954 NFL games (2019-2025). The underdog’s is the rest. Where enough games closed at a line, what favorites actually won is beside it.
| Favored by | Favorite wins | Underdog wins | Favorites actually won |
|---|---|---|---|
| 1 point | 53.9% | 46.1% | |
| 1.5 points | 55.8% | 44.2% | |
| 2 points | 57.7% | 42.3% | |
| 2.5 points | 59.6% | 40.4% | |
| 3 points | 61.5% | 38.5% | 59.0% of 668 |
| 3.5 points | 63.3% | 36.7% | |
| 4 points | 65.2% | 34.8% | |
| 5 points | 68.7% | 31.3% | |
| 6 points | 72.1% | 27.9% | |
| 7 points | 75.2% | 24.8% | 74.5% of 306 |
| 8 points | 78.2% | 21.8% | |
| 9 points | 81.0% | 19.0% | |
| 10 points | 83.5% | 16.5% | 87.4% of 135 |
| 11 points | 85.8% | 14.2% | |
| 13 points | 89.7% | 10.3% | |
| 14 points | 91.4% | 8.6% | 89.1% of 55 |
| 17 points | 95.1% | 4.9% | |
| 20 points | 97.4% | 2.6% |
How it’s calculated
The final margin is close to normal around what’s expected: the current lead plus the part of the pre-game line the rest of the game is worth. Its spread shrinks with the time left:
P(win) = Φ((lead + 1.81 · line · t/60) / (18.6 · √(max(t, 5.4)/60)))
with t the minutes left. The three numbers are fitted by maximum likelihood on 282,281 snaps of 1,954 games, 2019-2025, each game counted once. Checked against what happened, sorted into tenths by its own prediction:
| Predicted | Won |
|---|---|
| 1.9% | 2.3% |
| 11.8% | 11.8% |
| 23.4% | 22.5% |
| 34.1% | 33.6% |
| 44.3% | 43.6% |
| 55.7% | 56.4% |
| 65.9% | 66.4% |
| 76.6% | 77.5% |
| 88.2% | 88.2% |
| 98.1% | 97.7% |
It leaves out who has the ball and where: a team driving at the opponent’s 10 is worth about five points more than the score says. Our game pages’ win-probability charts include that (nflfastR’s), and every game page shows the pre-game line’s probability as “before kickoff”. What the line can’t tell you is how the game was actually played: that’s the replay on each game page, and the difference is the luck. How we measure luck
Questions
What is a 7-point favorite’s chance of winning in NFL?
About 75% by the model; in the games themselves (2019-2025), 7-point favorites won 74.5% of 306. Seven is one of football’s key numbers, so the real rate sits a little off the smooth curve.
How is win probability calculated from the point spread?
The final margin is close to normal around the line, with a spread of about 18.6 points over a whole game that shrinks with the time left. The chance of winning is the share of that curve above zero.