How Baseball Innings Work
Outs, innings and switching sides — a 5-minute hands-on for anyone new to baseball.
📖 In one sentence: when the defense gets the batting team out 3 times, the two teams switch between batting and fielding. Once both teams have batted, that's 1 inning. Repeat for 9 innings and the team with more runs wins!
Scoreboard: runs scored each inning stack up here. R = total runs.
How it works
Baseball splits into innings, and each inning has two halves. In the top half one team bats while the other fields; in the bottom half they swap. The fielding team's goal is to record 3 outs (a strikeout, a caught fly ball, and so on) — as soon as they do, the sides switch. When both teams have had their turn at bat, one inning is complete; a full game is 9 of them. While a team bats, hits move the batter and any runners around the bases (1st → 2nd → 3rd → home), and every runner who reaches home scores a run. This trainer runs a short 3-inning game so you can feel the rhythm: press "Bat!", watch the outs pile up, see the sides switch, and follow the runs stacking on the scoreboard. After a few games the play-by-play on TV — "bottom of the 7th, two outs, runner on second" — will finally make sense.
Frequently asked questions
What exactly is an "inning"?
An inning is one full round where both teams get a turn to bat. The team batting first plays the "top" of the inning; the other team plays the "bottom". A standard professional game has 9 innings.
Why do the teams switch?
The fielding team switches to batting once it records 3 outs against the batting team. Outs come from strikeouts, caught fly balls, and other plays. Three outs end that half-inning immediately.
How are runs scored?
A runner scores 1 run by advancing all the way around the bases and touching home plate. Hits move the batter and existing runners forward — a home run scores the batter and every runner at once.
Is this a real game or a simplified model?
It's a simplified teaching model. It runs a quick 3-inning game and focuses on the core flow — outs, switching sides, innings and runs — so beginners can grasp the structure. Real baseball adds balls, strikes, stealing, fielding positions and much more.