The balk field guide
Every way a pitcher can balk.
A balk is one of baseball's most misunderstood infractions. The rule book terminology can be confusing and difficult to translate. This site documents each balk type, how the rule books phrase it and includes video examples.
Pick a rule set
Official Baseball Rules
The Official Baseball Rules govern professional baseball and are the default rule set for most games played around the world.
Browse OBR balks →NCAA Baseball Rules
The NCAA Baseball rules govern collegiate play in the United States. Their pitching and balk provisions closely track OBR, with a handful of wording differences and a few college-specific wrinkles.
Browse NCAA balks →NFHS Baseball Rules
The National Federation of State High School Associations (NFHS) governs high school baseball in the United States. Its pitching rules differ substantially from OBR — most notably in how the set and windup positions are defined — so balks that look identical on the field are often written very differently in the NFHS book.
Browse NFHS balks →