What is a Double in Baseball? Definition and Examples
A double is a base hit on which the batter reaches second base safely without the aid of an error or a fielder's choice, and it counts as two total bases toward slugging percentage.
What is a Double?
A double is a base hit that allows the batter to reach second base safely, without benefiting from an error or a fielder's choice. It is the most common type of extra-base hit in baseball — MLB teams average roughly 1.6 doubles per game — and it sits between the single and the triple in both value and frequency. Doubles are scored as "2B" in the box score and count as two total bases.
A double can happen several ways: a line drive into the gap that rolls to the wall, a fly ball off the outfield fence, a ground ball down the line that kicks into the corner, or a bloop that splits two converging outfielders. What matters for scoring is only where the batter ends up — if he reaches second on his own hit, it's a double.
How a Double is Scored and Counted
The official scorer credits a double when the batter reaches second base entirely because of the hit. If the batter would have been out at second had an outfielder fielded the ball cleanly, the scorer rules a single plus an error instead. If the batter stops at first but advances when the defense throws behind a runner, that's a single plus advancement, not a double.
Doubles feed directly into the core batting stats:
- Slugging percentage (SLG): a double counts as 2 total bases. SLG = (1B + 2×2B + 3×3B + 4×HR) / AB.
- Isolated power (ISO): SLG minus batting average; doubles are the biggest single contributor to ISO for most hitters.
- wOBA: a double carries a linear weight of roughly 1.24–1.29 depending on the season's run environment, versus ~0.88 for a single.
Worked Example: Freddie Freeman
Freddie Freeman is the modern doubles king. In 2023 with the Dodgers he hit 59 doubles — the most in a season since 1936 — alongside a .331 average and 29 home runs. Those 59 doubles alone contributed 118 total bases, roughly a third of his 361 total bases on the year, and drove his .567 slugging percentage. For his career, Freeman passed 500 doubles, putting him in all-time top-30 territory. The all-time single-season record is Earl Webb's 67 doubles for the 1931 Red Sox; Tris Speaker holds the career record with 792.
Why Doubles Matter
Doubles are the best proxy for "gap power" — the ability to drive the ball into the alleys without needing home-run loft. Front offices treat doubles as a leading indicator: young hitters who hit 35+ doubles in the minors frequently convert some of those into home runs as they add strength, which is why a 21-year-old with 40 doubles in Double-A gets scouts excited. In fantasy baseball, doubles count directly in total-bases and extra-base-hit leagues and boost slugging in points formats. Doubles also matter for run production: a runner on first scores on a double roughly 40% of the time, making it the most efficient rally-extending hit short of a homer.
Limitations and Common Misconceptions
Doubles are heavily park-dependent. Fenway Park's Green Monster turns routine fly balls into doubles, while spacious outfields like Coors Field's produce doubles on balls that would be outs elsewhere — park factors for doubles vary by more than 20% between venues. A double also isn't always a well-struck ball: a 70-mph bloop down the line counts the same as a 110-mph rocket off the wall. That's why analysts pair raw doubles with expected slugging and hard-hit rate to judge whether the doubles are sustainable.
Related Terms
In Legends Deck: Doubles feed directly into a hitter card's power rating. Cards built on Statcast gap-to-gap data — high line-drive rate, strong exit velocity to the alleys — produce more simulated doubles, making Freeman-style hitters valuable even when their home-run totals look modest.