WHIP formula
WHIP = (walks + hits) ÷ innings pitched. It measures how many batters reach base by a walk or hit per inning, so lower is better.
Innings pitched use box-score notation: each out is a third of an inning, so 6.1 means 6⅓ innings and 6.2 means 6⅔. The calculator converts these before dividing.
Worked example
A pitcher allows 2 walks and 5 hits in 6.2 innings. Innings = 6 + 2 ÷ 3 = 6.667. WHIP = (2 + 5) ÷ 6.667 = 1.05.
Over a season, 50 walks and 150 hits in 180.1 innings gives 200 ÷ 180.333 = 1.11.
What WHIP leaves out
Standard WHIP counts only walks and hits. Batters hit by a pitch, reaching on an error or on a fielder's choice are not included, and WHIP says nothing about extra-base hits or runs.