Ultimate Fighting Calendar

MMA Power Index

How accurate are UFCalendar's MMA fight predictions?

How the model's pre-fight probabilities actually fared, graded against every decided fight in the database. Nothing is cherry-picked: these are the same numbers shown on bout pages before each fight, recomputed live.

UFCalendar's Power Index has correctly picked the winner in 62.6% of the 19470 MMA fights graded so far, with a Brier score of 0.239. It is well calibrated: when the model gives a fighter a 50%-55% chance, that favorite wins 56.9% of the time.

Favorite accuracy
62.6%
Fights graded
19470
Brier score
0.239

Calibration

When the model says 70%, does the favorite actually win about 70% of the time? Predicted vs. observed, by confidence bucket.

Model saysAvg predictedFavorite wonFights
50%55%52.2%56.9%6874
55%60%57.4%58.4%5285
60%65%62.4%66.1%3773
65%70%67.3%72.3%2241
70%75%72.2%78.2%1330
75%80%77.2%78.1%570
80%100%82.9%82.4%267

Accuracy by year

YearFightsAccuracy
2026102361.1%
2025181560.6%
2024177561.7%
2023177963.1%
2022149664.2%
2021143963.1%
2020105164.1%
2019146360.4%
2018125061.8%
2017104963.1%
201695564.5%
201578060.8%
201475465.1%
201350464.9%
201240761.4%
201133561.2%
201027563.6%
200923060%
200824164.3%
200719566.2%
200617165.5%
20059270.7%
20044650%
20033959%
20025267.3%
20013850%
20004271.4%
19993959%
19982369.6%
19972965.5%
19963562.9%
19952770.4%
19941877.8%
1993366.7%

Every number on this page is recomputed live from the stored pre-fight probabilities, the same ones printed on bout pages before each fight happens. Draws are excluded (no verdict to grade) and dead-even 50/50 prices grade no pick. Ratings and probabilities span every organization we track, back to 1993.