K%
Strikeout rate against — share of opposing PA that end in a strikeout.
What K% means
Pitcher version of K%; more stable than K/9 because it normalizes for batters faced rather than innings.
What counts as a good K%
Higher is better — roughly .200 is poor, .230 average, .270 good, and .320 or better elite.
Also written
k_rate_p · pitcher_k_pct · lg_k_pct · Lg K%