What this calculator does
Goals against average is goals allowed divided by minutes played, multiplied by sixty. It expresses how many goals a goaltender concedes per full game. Ninety goals over 3,600 minutes gives a GAA of 1.50.
The scaling matters for reading the number: 3,600 minutes is sixty full games, so this is a season figure rather than a single game. Enter a single game instead, say 3 goals in 60 minutes, and the GAA is simply 3.00, because one game at that rate is the rate.
The formula
Goals allowed are divided by minutes played and multiplied by sixty, which is the length of a regulation game. The calculation works at any scale: a single game, a month or a full season all give a comparable per-game rate, which is the point of the scaling.
| Term | Meaning |
|---|---|
| GAA | Goals against average, goals conceded per sixty minutes played. |
| Minutes played | Time actually on the ice, which is less than the games played if the goalie was pulled or substituted. |
| Save percentage | The alternative measure, which does not depend on how many shots the defence allows. |
| Empty net | Goals conceded with the goalie pulled are excluded from GAA. |
The inputs explained
| Field | What to enter |
|---|---|
| Goals allowed | Goals allowed. |
| Minutes played | Minutes played. A full regulation game is 60, and a full 82-game season around 3,600 for a starter. |
When to use it
Reading a season line
GAA appears alongside save percentage in every goaltending line and is the more familiar of the two to casual followers.
Assessing a single game
A single game GAA is just the goals conceded if the goalie played the full sixty minutes, which makes it trivially readable at that scale.
Comparing against save percentage
Where the two disagree, the difference is usually about shot volume, which is a statement about the defence rather than the goalie.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
What GAA does each season total give?
A full starter season of minutes against a range of goals allowed.
| Goals allowed | Goals against average | Goals allowed | Minutes played |
|---|---|---|---|
| 90 | 1.50 | 90 | 3,600 |
| 120 | 2.00 | 120 | 3,600 |
| 150 | 2.50 | 150 | 3,600 |
Questions
What is a good GAA?
In the NHL, under 2.50 is good and under 2.00 over a full season is exceptional. The figures shift with era and with rule changes affecting scoring, so comparing a modern GAA against one from the 1980s is misleading without adjustment.
Is GAA or save percentage the better measure?
Save percentage, for judging the goalie. GAA depends on how many shots the defence allows, so a goalie behind a strong defensive team posts a better GAA without playing any better. Save percentage measures what happened to the shots actually faced.
Are empty net goals counted?
No. A goal scored into an empty net is not charged to the goalie, since they were not on the ice. Including them would penalise a goalie for a coaching decision made while they were on the bench.
Why multiply by sixty?
To scale the rate to a full regulation game, which makes it interpretable against a scoreline. Without it the figure would be goals per minute, a small decimal that conveys nothing at a glance.
For save percentage, see the save percentage calculator. For the baseball equivalent, see the ERA calculator.