How this calculator works
OPS is a quick summary that gives a walk the same value as a single. OBP captures reaching base and SLG captures power, and adding them produces a number that correlates well with run scoring even though the two components have different scales. In counting-stats mode the calculator derives singles as hits minus doubles, triples and home runs, then sums total bases. In solve mode it subtracts the known component from OPS. OPS overweights slugging slightly, which is why more detailed measures such as weighted on-base average exist, but it remains easy to read and widely published.
Formula
OPS = OBP + SLG. OBP = (H + BB + HBP) / (AB + BB + HBP + SF). SLG = TB / AB, where TB = singles + 2 x doubles + 3 x triples + 4 x home runs. Solving for a component: SLG = OPS - OBP or OBP = OPS - SLG.
Worked example
A batter has 160 hits, 30 doubles, 4 triples, 25 home runs, 60 walks, 5 hit by pitches, 550 at-bats and 3 sacrifice flies. Singles are 101 and total bases are 273. SLG = 273 / 550 = 0.496, OBP = 225 / 618 = 0.364, and OPS = 0.860. If OPS is 0.860 and OBP is 0.364, SLG is 0.496.
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Frequently asked questions
Why can OPS be above 1?
The two components are fractions, so a very strong season can add up to more than 1.000. An OPS of 1.000 is excellent even though a batting average of 1.000 would be extraordinary.
Does OPS include sacrifice flies?
Sacrifice flies count in the OBP denominator and in plate appearances, but not in at-bats or in slugging. They do not add a hit.
What is the difference between OPS and wOBA?
OPS treats every point of OBP and SLG as equally valuable. Weighted on-base average uses run values for each event, so it gives a walk less credit than a home run and is a better estimate of offensive value.