How Many Innings Are in a Baseball Game? (9 in MLB)

A standard baseball game has nine innings, each made up of a top half (the visiting team bats) and a bottom half (the home team bats). That’s the rule in Major League Baseball, the minor leagues, college baseball, and the World Series. High school games are seven innings, Little League is six, and if the score is tied after the final inning, the game goes to extra innings until someone wins. A typical MLB game lasts about two hours and 40 minutes.

What is an inning in baseball?

An inning is a single round of play in which both teams get a turn to bat and a turn to play defense. The visiting team bats first in the top of the inning, trying to score while the home team pitches and fields. Once the visiting team makes three outs, the teams switch: the home team bats in the bottom of the inning while the visitors take the field. An inning isn’t complete until both halves are played — unless the home team is already ahead and doesn’t need to bat in the ninth.

Every pitch, at-bat, and defensive play happens inside this top-half/bottom-half structure, which is why an inning is called baseball’s basic building block — the way a quarter works in football or a period works in hockey.

How many innings at each level of baseball

The number of innings depends on the level of play:

Level	Standard innings	Notes
MLB (Major League Baseball)	9	Extra innings if tied
Minor League Baseball	9	7 per game in doubleheaders
College baseball (NCAA)	9	7 in doubleheaders; mercy rule after 7
World Series	9	Best-of-seven series
High school baseball	7	Some states use fewer for JV
Little League (Majors, ages 9-12)	6	Younger divisions play fewer
Tee Ball / Coach Pitch	3-6	Varies by local league
Softball	7	High school, college, and Olympic
International (WBSC)	9	Mercy rule after 7 (10-run lead)

Nine innings is the sport’s benchmark because it’s what MLB, its minor league affiliates, most college programs, and the postseason all use. Everything shorter exists to fit youth attention spans, school schedules, and pitcher workload limits.

How long is a baseball game?

A nine-inning MLB game lasts about two hours and 40 minutes on average. That number dropped sharply after the 2023 season, when MLB introduced a pitch clock — pitchers now have a limited number of seconds to deliver each pitch — which cut roughly 25 minutes off the previous average of just over three hours.

Game length still varies a lot because baseball has no clock on the action itself:

• A low-scoring, fast-paced game can finish in well under two and a half hours.
• A high-scoring game full of walks, hits, pitching changes, and mound visits can run past three and a half hours.
• Extra innings add time in unpredictable chunks.

A single inning has no set length either — it ends after three outs per side, so it averages roughly 15 to 20 minutes but can stretch much longer when the bats get going. Minor league games run slightly shorter than MLB on average, and youth games are far shorter simply because they play fewer innings.

What happens if the score is tied

If the game is tied after nine complete innings, it goes to extra innings. Play continues one inning at a time — each with its own top and bottom half — until one team leads after a completed inning, or the home team takes the lead in the bottom half, which ends the game immediately (a walk-off). There is no clock and no shootout in baseball.

To keep extra innings from dragging on, MLB added the automatic runner (nicknamed the “ghost runner”) in 2020: each team starts every extra half-inning with a free runner on second base, making it much easier to score. It’s permanent in the regular season but is not used in the playoffs — see our full breakdown of the ghost runner rule.

Before that rule, extra innings could go on almost indefinitely. The longest MLB game by innings was a 26-inning tie between Brooklyn and Boston in 1920, while the longest by time was a 25-inning, 8-hour-6-minute White Sox win over the Brewers in 1984. The longest professional game overall was a 33-inning minor league marathon between the Pawtucket Red Sox and Rochester Red Wings in 1981, played across two days.

When a game ends before nine innings

A few situations end a game early:

• Mercy rule (run rule): If one team leads by 10 or more runs after a set number of innings — commonly seven in college, or five in some youth and amateur leagues — the game ends automatically so lopsided games don’t drag on.
• Weather or field conditions: A game called for rain or unsafe conditions becomes an official game once five innings are complete (or 4.5 if the home team is leading), with the result based on the score at the stoppage. Called earlier than that, it’s usually suspended or replayed.
• Walk-off finish: If the home team is already ahead after the visitors bat in the ninth (or any extra inning), it doesn’t need to take its turn at bat, and the game ends right there.

Why nine innings became the standard

Baseball didn’t always use nine innings. In the 1850s, some clubs played to a set number of runs — often first team to 21. As the sport professionalized through the 1860s and into the founding of the National League in 1876, nine innings became the accepted structure and has stayed that way ever since. Pitch clocks and other pace-of-play rules have changed how long an inning takes, but not how many are played.

How many games are in a baseball season?

Innings measure a single game; the season is measured in games. Each MLB team plays a 162-game regular season from late March or early April through the end of September — one of the longest schedules in pro sports. After that, up to 12 teams reach the postseason, a ladder of best-of-three Wild Card series, best-of-five Division Series, best-of-seven League Championship Series, and the best-of-seven World Series. For the full bracket, see how the MLB playoffs work and how the MLB wild card works.

How many baseballs are used in a game?

More than most fans expect. An MLB game runs through roughly 90 to 120 baseballs. A ball is taken out of play the moment it’s fouled into the stands, scuffed, hit in the dirt, or used for a while, so teams prepare well over 100 per game. Before the game, each ball is rubbed with a special mud to take off the factory shine and give pitchers better grip.

Innings vs. outs: the real building blocks

The key thing to remember is that an inning isn’t an amount of time — it’s defined by outs. Each half-inning ends after three outs, which means six outs make one full inning, no matter how many pitches it takes. That’s why “nine-inning” games vary so much in length, and why the count on the batter — like a full count of three balls and two strikes — matters so much for how quickly outs come. It also defines the strike zone battle that drives every at-bat, and it’s the denominator behind pitching stats like ERA, which measures earned runs per nine innings.

Related baseball rules and terms

Understanding innings is the entry point to the sport’s structure. From here, learn the nine defensive positions by number, why the designated hitter bats in place of the pitcher, and the rare feat of a perfect game across all nine innings. For every term in one place, use our baseball terminology glossary, and for more explainers, browse our full baseball and MLB coverage.