WAR Calculator (Baseball) Calculator

The wOBA-based wRAA calculation is a per-plate-appearance rate scaled up by total plate appearances, so more PA at the same rate of production produces more total batting runs. The replacement-level adjustment (20 runs per 600 PA) also scales with plate appearances, but since it's a fixed positive addition rather than tied to your actual performance, the net effect of more playing time at a good wOBA is a higher WAR — reflecting that a player who sustains good performance over more games provides more total value.

These three inputs are added directly into total runs above replacement before dividing by the runs-per-win constant, so at their default of 0 the calculator's WAR is purely a batting-runs estimate. If you have real defensive metrics (like DRS or UZR) or a baserunning value (like BsR) for the player, entering them here adds that value on top of batting runs for a more complete WAR figure — a positional adjustment is also worth adding since it accounts for the fact that a shortstop's defensive value is worth more than a first baseman's at the same skill level.

This calculator uses fixed constants — a league-average wOBA of .320, a wOBA scale of 1.25, and 10 runs per win — that are actually recalculated every season by the official sites based on the real run-scoring environment, and it has no park-factor adjustment at all. Those published sites also use much more granular fielding data (like Statcast-based metrics) than the single Fielding Runs number this calculator accepts, so expect the two figures to be in the same neighborhood but not identical.

OBP uses hits plus walks plus hit-by-pitch divided by at-bats plus walks plus sacrifice flies plus hit-by-pitch — the same denominator wOBA uses, since both are on-base-style rate stats. SLG, however, divides total bases by at-bats alone, since slugging percentage specifically measures power production per official at-bat and doesn't credit walks or hit-by-pitches, which aren't at-bats. OPS is then just OBP plus SLG added together.