IntermediatePitching
K-BB%
Strikeout Rate Minus Walk Rate
A pitcher's strikeout rate minus his walk rate: how many more strikeouts than walks per 100 batters faced.
13.3%2026 MLB average (2025: 13.8%)
Simple explanation
A strikeout is an out the pitcher gets with no help from the defense, and a walk is a runner he puts on all by himself. Neither involves much defense or luck, so together they say a lot about the pitcher himself.
A 25% strikeout rate and a 7% walk rate make an 18% K-BB%. A pitcher who piles up strikeouts but walks just as many gets marked down, and one with few strikeouts can hold up if he almost never walks anyone.
Benchmarks
- 9.3%
- Bottom 10%
- 16.8%
- Median
- 23.4%
- Top 10%
Distribution of the 46 qualified pitchers in 2026.
Detailed explanation
K-BB% = K% − BB%
- K%
- strikeouts ÷ batters faced
- BB%
- walks ÷ batters faced
It's just one rate minus another, but it's a strong predictor of the rest of a season. FanGraphs' Stuff+ primer says as much and uses K-BB% as the benchmark for its own Pitching+ model.
It ignores contact quality entirely. A pitcher who gets out of innings with ground-ball double plays, or one who lives on weak fly balls, gets undersold.
The denominator is batters faced, so it isn't the same as K/9 minus BB/9. League average fell to 13.3% in 2026 from 13.8% in 2025, in step with the rise in walks.