LOB (Left on Base) Calculator
Definition – What is LOB%?
LOB shows the average number of runners a pitcher leaves on base.
The metric creates the result from box score information. It is not the tally of the number of baserunners left at the end of the inning.
Some statisticians have noted that most pitchers have a LOB% that tends to regress to the low 70% over time.
Formula – How to calculate LOB%
LOB% = (Hits + Walks + Hit by Pitch – Runs) ÷ (Hits + Walks + Hit by Pitch – (1.4 x Home Runs))
Example
If a pitcher has allowed 190 hits, 43 walks, hit 3 batters, allowed 69 runs, and 19 home runs, then:
LOB% = (190 + 43 + 3 – 69) ÷ (190 + 43 + 3 – (1.4 x 19))
LOB% = 167 ÷ (190 + 43 + 3 – 26.6)
LOB% = 167 ÷ 209.4
LOB% = 0.7975
This pitcher’s LOB% is 0.7975, or 79.75%. 79.75% of runners on base are left on base at the end of the inning when facing this pitcher.
Sources and more resources
- Wikipedia – Baseball Statistics – Wikipedia entry on baseball statistics.
- Glossary Entry from FanGraphs.
- Rules on baseball and baseball statistics from Major League Baseball, NCAA (Baseball), NCAA (Softball), NCAA (Baseball and Softball), NFHS, and the International Baseball Federation.