What is strikeout rate?
K/9 is strikeouts per nine innings; K% is strikeouts per batter faced. K% is the modern analyst's choice because it does not reward pitchers who can't get anyone else out — but K/9 remains the fantasy currency.
How the calculator works
K/9 = 9 × K ÷ innings (thirds notation handled). Add batters faced and the tool also returns K%, the share of opponents struck out.
Common use cases
- Fantasy drafting: strikeout ceilings drive ceiling
- Prospect progression tracking
- Separating swing-and-miss stuff from pitchability
Formula & context
9.0 K/9 is above average, 10+ is a power arm, and 12+ is the ace tier. K% above 27% for starters is elite company.
Frequently Asked Questions
K/9 or K% — which is better?
K% is analytically fairer (it accounts for how many batters a pitcher faces); K/9 is more traditional.
What is a good K/9?
9.0+ is above average; 12+ is the ace tier.
Why do strikeouts matter so much in fantasy?
They are the most stable counting category and don't depend on defense or park.
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