Ice Hockey Goals Against Average Calculator
Ice Hockey Goals Against Average Calculator
Goals against, scaled to a full ice hockey game. The NHL’s formula is GA x 60 / time on ice, and the 60 comes from three 20-minute periods — so the period length is an input here rather than a constant.
Goals against average
Per full game155 goals against in 3,293.25 minutes of play, three 20-minute periods — Spencer Knight’s 2025-26 NHL regular season
Formula
- GAA = GA*60/time on ice
- the NHL’s own formula, printed verbatim in its statistics glossary, which describes the quantity as “the average number of goals that a goaltender gives up per game, measured in 60-minute increments”. The 60 is not a universal constant: it is three 20-minute periods, and this page makes it an input so the arithmetic still works where a game is not 60 minutes
- three periods of twenty minutes
- IIHF Rule 77.1, 2026/27 rule book: “The time allowed for a game shall be three (3) twenty-minute (20) periods of actual play with a rest intermission between”. Rule 77.2 sets the intermission at 15 minutes or another length the IIHF designates
- minutes of play
- actual playing time. The clock stops at every whistle, so playing time and elapsed time differ by a long way. The NHL publishes time on ice in SECONDS, so divide by 60 before entering it here
- what does not belong in the numerator
- shootout goals, because under IIHF Rule 84.4 the shootout decides the game and only the decisive goal counts, and goals conceded into an empty net after the goaltender has left the ice, because they are not conceded while the goaltender is on it
- not the field hockey number
- field hockey’s full match is also 60 minutes, and has been since 1 September 2014 — but the two 60s are arrived at completely differently, four 15-minute quarters under the FIH against three 20-minute periods under the IIHF, and the coincidence is not a reason to compare the numbers. A pre-2014 field hockey average is on a 70-minute base and matches nothing at all
Worked example
155 goals against in 3,293.25 minutes of play, three 20-minute periods — Spencer Knight's 2025-26 NHL regular season
3,293.25 ÷ 60 = 54.89 full games of playing time
155 × 20 × 3 ÷ 3,293.25 = 2.82 goals per full game, which is one goal every 21.2 minutes of play
The NHL publishes 2.82395 for this goaltender in 2025-26 from 155 goals against and 197,595 seconds on the ice, and 155 × 3600 ÷ 197,595 = 2.8239581. The league's figure is truncated to five places, not rounded
Now the degeneracy test, which is the reason the format is an input. At three 20-minute periods the headline and the per-60 figure are both 2.82 — equal by construction, so a hard-coded 60 would pass every check available here. Change the period length to 15 and the headline becomes 2.12 while the per-60 figure stays 2.82. They have to separate, and if they do not, the arithmetic is wrong
Double both the goals and the minutes — 310 goals in 6,586.5 minutes — and the answer stays 2.82. Halve the minutes to 1,646.625 and it doubles to 5.65. It is a rate
Enter 0 minutes and the calculator returns no value: no goals in no minutes is not an average of zero. Zero goals over real minutes does give 0.00, which is a shutout and a real answer
The same pair of goaltenders, read from the other end
| Goaltender, 2025-26 NHL regular season | Goals against | Minutes of play | Goals-against average | Shots faced per 60 min | Save % |
|---|---|---|---|---|---|
| Spencer Knight | 155 | 3,293.25 | 2.82 | 28.84 | 90.2 |
| Linus Ullmark | 131 | 2,883.47 | 2.73 | 24.93 | 89.1 |
What a full game is, and who says so
| Format | Periods | Minutes of play | Source |
|---|---|---|---|
| International ice hockey | Three periods of 20 minutes | 60 | IIHF Rule 77.1, IIHF Rule Book 2026/27 |
| NHL goals-against average | Scaled in 60-minute increments | 60 | the NHL’s own statistics glossary, which gives GAA = GA*60/time on ice |
| IIHF overtime, round robin | One period of up to 5 minutes, sudden death | up to 5 | IIHF Rule 84.1 — three skaters and a goalkeeper per side |
| Youth and recreational hockey | Shorter periods, commonly three | varies | your own competition’s playing conditions; neither the IIHF nor the NHL publishes a figure |
Why the divisor has to be an input
This page is about ice hockey — the game played with a puck on an ice rink, whose international rules are the IIHF’s and whose North American professional rules are the NHL’s own. It is not about field hockey, the eleven-a-side game on a turf pitch governed by the FIH, whose periods, set pieces and statistical definitions are different; this site keeps the two sports in separate sections for that reason.
A full game is 60 minutes of play. IIHF Rule 77.1 in the 2026/27 rule book puts it exactly: “The time allowed for a game shall be three (3) twenty-minute (20) periods of actual play with a rest intermission between”. The NHL’s own glossary scales the same way, defining goals-against average as a figure “measured in 60-minute increments”. That is actual playing time, not elapsed time: the clock stops at every whistle, so a 60-minute game takes about two and a half hours.
A goals-against average takes the goals a goaltender conceded and scales them to one full game, which means the figure cannot be computed without deciding how long a full game is. In senior ice hockey that decision is easy and invisible — it is 60 minutes under both bodies — and that is exactly what makes it dangerous to hard-code. At 60 minutes the headline figure and the per-60 figure are the same number by construction, so an implementation that assumed 60 would agree with itself perfectly and say nothing. Change the period length to 15 and the two separate: 155 goals in 3,293.25 minutes is 2.82 per 60-minute game and 2.12 per 45-minute one. If they do not separate, the arithmetic is wrong, and that is the only test available.
This figure depends heavily on how many shots the team in front of the goaltender allows, and that is the main criticism of it. Two goaltenders who stop the same share of the shots they face will have different goals-against averages if one faces more shots, and the one who faces fewer looks better without having done anything better. Save percentage is generally the preferred figure for that reason, and the two can disagree about which of two goaltenders had the better season. The table above is a real pair, from the league’s own 2025-26 totals, where they do exactly that. The save percentage page sets out the NHL’s definitions of the shots and saves behind both, and works the same pair from the other end.
A note on how the period length is sourced. The NHL serves its Official Rules as a PDF, and the text extraction available here stops a quarter of the way in, before Rule 86, “Start of Game and Periods”. So the 20-minute period here is quoted from the IIHF’s rule book, which could be read in full, and corroborated by the NHL’s own glossary scaling goals-against average in 60-minute increments. The two bodies agree; the NHL’s own sentence saying so is not quoted here because it was not read. For what the points in the standings depend on, including why an overtime game is worth more points in total than a regulation one, see the standings points page.
Frequently asked questions
How is goals against average calculated in ice hockey?
The NHL’s own formula is GAA = GA*60/time on ice: goals against, times 60, divided by the minutes played. 155 goals in 3,293.25 minutes is 2.82. The 60 is three 20-minute periods, which is why this page lets you change it rather than treating it as a constant.
How long is an ice hockey game?
Sixty minutes of actual play. IIHF Rule 77.1 of the 2026/27 rule book reads “three (3) twenty-minute (20) periods of actual play with a rest intermission between”, and Rule 77.2 sets the intermission at 15 minutes or another length the IIHF designates. Because the clock stops at every whistle, 60 minutes of play takes about two and a half hours.
Do shootout goals count in a goals against average?
No. Under IIHF Rule 84.4 the shootout settles a game that is still tied after overtime, with five shooters a side taking alternating shots, and only the decisive goal counts. None of it belongs in a goals-against average. Overtime goals, on the other hand, do count, and overtime minutes count as time on ice.
Is a goals against average better or worse than a save percentage?
Generally worse as a measure of the goaltender, because it depends on how many shots the team allows. The two can disagree outright: in 2025-26 Ullmark’s 2.73 beat Knight’s 2.82 while Knight’s save percentage beat Ullmark’s.
Is this the same as a field hockey goals against average?
The arithmetic is the same and the divisor now happens to agree, because field hockey’s match has been 60 minutes since 1 September 2014 — but it gets there as four 15-minute quarters under the FIH rather than three 20-minute periods under the IIHF, and an FIH figure from before that date is on a 70-minute base. The coincidence of the divisor is not a reason to compare the numbers, and a field hockey shot total has no FIH definition behind it at all.
Related calculators
References
- National Hockey League. NHL Stats Glossary, served as JSON at api.nhle.com/stats/rest/en/glossary (read 12 Oct 2026; 103,774 characters). The league’s own definitions and formulas, quoted verbatim wherever this site states one. nhl.com itself is robots-disallowed, and edge.nhl.com/en/glossary redirects to a page with no definitions on it.
- National Hockey League. Goaltender season summaries, 2025-26 regular season, as JSON at api.nhle.com/stats/rest/en/goalie/summary (read 12 Oct 2026). Time on ice is published in seconds. Both formulas were reproduced from the raw counts for 29 goaltenders of 40 or more games. Note that savePct is published TRUNCATED to five decimal places, not rounded.
- International Ice Hockey Federation. IIHF Rule Book 2026/27. Zurich: IIHF; 2026. Served article by article at test.rulebook.iihf.com (read 12 Oct 2026; rulebook.iihf.com is robots-disallowed). Rules 1.1, 1.2, 1.5, 77.1 to 77.3 and 84.1 to 84.6. Rule 1.2’s dimensions are in the rule text, not only in the Appendix VI infographic, which was checked.
- National Hockey League. 2024-2025 Official Rules. New York: NHL; 2024. PDF at media.nhl.com. Rules 1.2, 16.1, 18.1, 20.1 and 23 are quoted from the extracted text, which stops at 128,456 characters partway through Rule 19.4 — so Rule 77 (p.118), Rule 84 (p.129) and Rule 86 (p.134) could not be read and are quoted nowhere in this batch; their page numbers come from the book’s own contents.