BB/9 Calculator
Definition – What is Walks per 9 Innings (BB/9)?
BB/9 shows how frequently a pitcher walks batters.
A lower BB/9 is considered better, as it means that the pitcher walks fewer batters in each inning pitched.
Formula – How to calculate BB/9
BB/9 = 9 x (Walks ÷ (Innings Pitched + (Outs (Partial Innings) Pitched / 3))
Example
If a pitcher has allowed 43 walks over 202 innings and 1 out, then:
BB/9 = 9 x (43 ÷ (202 + (1 / 3))
BB/9 = 9 x (43 ÷ 202.333333)
BB/9 = 9 x 0.2152
BB/9 = 1.913
Over an average of 9 innings, this pitcher will have walked 1.913 batters.
Sources and more resources
- Wikipedia – Walks per 9 Innings Pitched.
- Rules on baseball and baseball statistics from Major League Baseball, NCAA (Baseball), NCAA (Softball), NCAA (Baseball and Softball), NFHS, and the International Baseball Federation.