Plus-minus is a team-impact number for one player. It subtracts the points the other team scored while the player was on court from the points the player's team scored. A plus-minus of plus 12 means the team outscored opponents by 12 points during that player's minutes. A negative number means the team was outscored.
This free calculator works out three plus-minus numbers: total plus-minus, plus-minus per game, and plus-minus per 36 minutes. Enter team points scored and conceded while the player was on court, plus minutes played and games. The tool shows all three instantly, with no sign-up and no download. Everything runs in your browser.
The formula is simple. Plus-minus equals points for minus points against, counted only while the player is on the court. For example, 110 points for and 98 against gives plus 12. Over 5 games that is plus 2.40 per game. Per 36 minutes, which is close to a full game for a starter, it is plus 12 divided by 32 minutes, multiplied by 36, which is plus 13.50.
Why three numbers? Because totals favor players who play more. A bench player with plus 12 in 32 minutes had a bigger impact per minute than a starter with plus 12 in 180 minutes. Per-game figures fix the games difference. Per-36 figures fix the minutes difference. Together they let you compare a starter and a reserve fairly.
To use the tool, enter team points scored while the player was on court first. This is not the player's own points: it is the whole team's points during their minutes. Enter team points conceded the same way. Enter minutes played and games. Press calculate and read the three results, including the plus or minus sign.
How do you read the results? A positive plus-minus means the team wins the player's minutes. Above plus 5 per game is strong, and above plus 10 per game is outstanding. A negative number means the team loses the player's minutes, which is a warning sign, not a verdict: lineups matter hugely. A good player on a weak bench unit can carry a negative number through no fault of their own.
Coaches use plus-minus to find lineup effects. Two players may both average 15 points, but if one is plus 8 per game and the other is minus 4, the first player's minutes help the team more. Coaches also check pairs: which five players together produce the best plus-minus? Those answers shape rotations and closing lineups in tight games.
Context always matters. Plus-minus credits a player for teammates' work and blames them for teammates' mistakes, because it only sees the score while they share the court. Strong teams inflate everyone's numbers, and weak teams drag them down. Compare players on the same team first. Over a full season, the numbers become much more trustworthy than over a few games.
Common mistakes are easy to avoid. First, use team points, not the player's own points: a player who scores 20 while the team concedes 30 is minus 10, not plus 20. Second, count only minutes the player actually played. Third, never judge from one game: a single blowout can swing a small sample wildly, while a season average tells a steadier story.
Young players often ask how to improve plus-minus. The honest answer is defense and decision-making: defend your man, rotate on time, move the ball, and take good shots. Scoring more helps, but stopping the other team helps just as much. Use this calculator across a season to see whether your minutes truly help the team win, which is the question coaches care about most.
Versión en español: https://ilmhunt.com/calculadora-mas-menos-baloncesto/