How this calculator works
A shot on goal is a shot that would enter the net if the goaltender did not stop it. Saves divided by shots on goal gives save percentage. The index divides that value by a league average and multiplies by 100, so 100 is average, 105 is five percent better than average and 95 is five percent worse. Save percentage is a rate and can be noisy over a short sample: a few shots can move it by a noticeable amount.
Formula
Save percentage = saves / shots on goal. Saves = save percentage x shots. Shots = saves / save percentage. Index = (save percentage / league average) x 100.
Worked example
A goaltender makes 900 saves on 1,000 shots: 900 / 1,000 = 0.900, or 90.0 percent. If the league average is 90.5 percent, the index is 90.0 / 90.5 x 100 = 99.4, slightly below average.
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Frequently asked questions
Why is a higher save percentage better?
It is the share of shots stopped. A goaltender who stops 92 percent of shots allows fewer goals per shot faced than one who stops 90 percent, though the number of shots faced also matters.
How many shots make a reliable sample?
Save percentage settles slowly. A single game can swing it by several points, and analysts usually wait for hundreds of shots before treating a difference as meaningful. Compare with goals saved above expected when that data is available.
Does the index account for shot quality?
No. It only compares the raw rate with the league average you enter. Shot location, power plays and score effects all influence the number.