Strikeout Rate (K/9 & K%)
How often a pitcher records strikeouts per 9 innings (K/9) or per batter faced (K%).
Full Definition
K/9 measures strikeouts per nine innings while K% measures the percentage of batters faced who are struck out. K% is generally preferred because it accounts for pace and isn't inflated by pitchers who throw deep into games. High strikeout pitchers are valuable for NRFI bets (fewer balls in play in the first inning) and strikeout over props.
What's a good Strikeout Rate?
K/9 above 10.0 is elite, 8.5-10.0 is above average. K% above 27% is elite, 22-27% is above average.
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Read our in-depth guideRelated terms
Whiff Rate (Whiff%)
Percentage of swings that result in misses. Measures a pitcher's ability to generate swings and misses.
ERA (Earned Run Average)
Average earned runs a pitcher allows per nine innings. The standard measure of pitching effectiveness.
WHIP (Walks + Hits per Inning)
Walks plus hits allowed divided by innings pitched. Measures baserunner traffic.
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