Softball vs baseball

Normally 7 innings.

MLB: 9 innings. WBSC: 6, 7 or 9 depending on the event and age category.

Bases are 18.29 m apart. Adult pitching distance: 13.11 m for women and 14.02 m for men.

Standard bases: 27.43 m apart; pitching distance: 18.44 m. Youth fields may be smaller.

Underhand delivery from a flat plate; windmill pitching is permitted in fast pitch. Modified fast pitch has other restrictions.

The pitcher uses a raised mound and the windup or set position. The rules do not require every delivery to be overarm.

In this WBSC edition, remain on the base until the pitcher’s non-pivot foot touches the ground during the pitching movement.

Runners may take a lead before the pitch, but risk being picked off or tagged while off base.

A starting player may re-enter once in the same batting position. A replaced substitute cannot normally return.

In ordinary MLB and WBSC baseball, a removed player cannot return. A pinch-runner is a substitute.

Optional DP/FLEX: 10 listed players, 9 batting positions. The FLEX can bat only in the DP’s place; they cannot both play offense simultaneously.

The DH bats for the pitcher. Special pitcher-DH rules exist; this is not the softball DP/FLEX system. Some youth events do not use a DH.

From inning 8, each half-inning starts with a runner on second.

MLB regular season: runner on second from inning 10; no automatic runner in the postseason. The listed WBSC events start extra innings with runners on first and second.

A lead of 15 after 3 innings, 10 after 4, or 7 after 5 can end the game, with the home team’s corresponding batting opportunity preserved.

MLB has no general run-ahead ending. WBSC limits depend on the event; the listed World Cup provisions include exceptions for championship games.