K/BB
Strikeout-to-walk ratio — strikeouts divided by walks.
What K/BB means
The old-school companion to K-BB%. League average is roughly 2.6; above 4.0 is front-of-rotation command. K-BB% is the more stable version because it is scaled to batters faced.
How K/BB is calculated
K/BB = K / BB
What counts as a good K/BB
Higher is better — roughly 2 is poor, 2.6 average, 3.5 good, and 4.5 or better elite.
Also written
k_per_bb · strikeout_walk_ratio · kbb