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 62.9% of the 26659 MMA fights graded so far, with a Brier score of 0.235. It is well calibrated: when the model gives a fighter a 50%-55% chance, that favorite wins 55.2% of the time.

Favorite accuracy
62.9%
Fights graded
26659
Brier score
0.235

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%55.2%8957
55%60%57.4%59.7%7133
60%65%62.3%65.4%5167
65%70%67.3%72.6%3193
70%75%72.3%79.8%1869
75%80%77.2%81.4%867
80%100%83%81.8%352

Accuracy by year

YearFightsAccuracy
2026153161.1%
2025234362.4%
2024231863%
2023238663.3%
2022188264.9%
2021175363.4%
2020132264.2%
2019190261.9%
2018157761%
2017132463.4%
2016118562.3%
201595961.9%
201498163.8%
201374064.6%
201264860.8%
201166861.8%
201062961.2%
200947059.6%
200837261.6%
200731964.6%
200635567.6%
200521171.6%
200415862.7%
200310064%
200212166.1%
20019064.4%
20009376.3%
19996666.7%
19983961.5%
19973557.1%
19963464.7%
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.