An official Major League baseball weighs between 5 and 5 1/4 ounces, or about 142 to 149 grams, and measures 9 to 9 1/4 inches around. Those specifications have barely changed in more than a century, and the same size ball is used from Little League through the majors.
Equipment explained
Official baseball specifications
As set by the Official Baseball Rules
Weight
5 to 5 1/4 ouncesAbout 142 to 149 grams
Circumference
9 to 9 1/4 inches
Diameter
About 2.86 to 2.94 inches
Stitches
108 double stitchesSewn by hand with red waxed thread
Cover
Two figure eight pieces of cowhideHorsehide until 1974
Core
Cork and rubber centerWrapped in wool and cotton yarn
Youth baseball
Same size and weight in most leaguesSome youth leagues use softer balls for young players
12 inch softball
About 6 1/4 to 7 ouncesNoticeably heavier than a baseball
Specifications from the Official Baseball Rules.
Baseball vs. Other Balls
| Ball | Approximate weight |
|---|---|
| Baseball | 5 to 5 1/4 ounces |
| Fastpitch softball (12 inch) | 6 1/4 to 7 ounces |
| Tennis ball | About 2 ounces |
| Golf ball | About 1.6 ounces |
| Official NFL football | 14 to 15 ounces |
Why Weight Matters
Tiny differences in how a ball is wound change how far it carries, which is why MLB tests balls for bounce, called the coefficient of restitution, and stores them in humidors at every park. For what goes inside the ball, see what baseballs are made of.
Related
How many stitches on a baseball · What are baseballs made of · How many baseballs are used in a game · Why MLB rubs mud on baseballs
Specifications from the MLB official rules.