What Elo measures

Elo is an opponent adjusted rating built from every UFC fight since 1994, more than 8,500 bouts.

Everyone starts at 1500. After each fight the winner takes points from the loser, and the size of the move depends on how surprising the result was. Beating a much higher rated fighter moves the number a lot. Beating a much lower rated one barely moves it. Finishes count for slightly more than decisions.

This is what raw stats miss: strikes landed per minute cannot tell whether those strikes came against a contender or a short notice replacement. Elo can, because it only rewards you as much as the opponent was worth.

Rough scale: 1500 is average, above 1600 is the upper tier, and the very best sit near 1700. A 100 point gap works out to about a 64 percent win probability, 200 points to about 76 percent.

The star means that fighter has fewer than five UFC fights on record, so their rating has not settled yet and should carry less weight.