What does drop −10 mean on a baseball bat?
A −10 bat weighs 10 ounces less than its length in inches: a 30 in, −10 bat weighs 20 oz. The bigger the drop number, the lighter the bat for its length.
What "drop" means
Drop is length minus weight: a 30 in, 20 oz bat is a -10. A bigger drop number means a lighter bat for its length. Younger players use -10 to -13; USSSA 13U is usually capped at -5; high school and college are -3.
Check the drop your league allows before you look at anything else.
The drop by age
From the drop rules in the fit.
| Who | Drop |
|---|---|
| 4 to 6 | −14 to −10.5 |
| 5 to 7 | −13 to −12 |
| 8 to 12 | −12 to −10 |
| 13 to 14 | −5 |
| High school and College | −3 |
| 11 and under, wood | −8 to −7 |
| 12 to 13, wood | −5 |
| 14 and up, wood | −3 |
Where this comes from
- published Ages 4-6 (tee ball): JustBats - Bat Resource Guide
- published Ages 5-7: JustBats - How To Select The Right Bat Size for Kids
- published Ages 8-12: Louisville Slugger - How to Choose a Baseball Bat
- published Ages 13-14, USA or USSSA: Louisville Slugger - How to Choose a Baseball Bat
- published High school and college: USA Baseball - About USA BBCOR
- published Wood, age 11 and under: Phoenix Bats - How to Pick the Right Bat Size for Youth Ballplayers
- published Wood, ages 12-13: Phoenix Bats - How to Pick the Right Bat Size for Youth Ballplayers
- published Wood, age 14 and up: Tater Baseball - How to Choose a Wood Bat
- Our explainer: What "drop" means
Every rule, with its source, is on How the fit works.
More in bat guides
- What size bat for a 7-year-old?A 7-year-old usually swings a −13 to −12 bat.
- What size bat for an 8-year-old?An 8-year-old usually swings a −12 to −10 bat.
- What size bat for a 9-year-old?A 9-year-old usually swings a −12 to −10 bat.
- What size bat for a 10-year-old?A 10-year-old usually swings a −12 to −10 bat.
- What size bat for an 11-year-old?An 11-year-old usually swings a −12 to −10 bat, or −8 for a bigger, stronger player.
- What size bat for a 12-year-old?A 12-year-old usually swings a −12 to −10 bat, or −8 for a bigger, stronger player.
- What size bat for a 13-year-old?A 13-year-old usually swings a −5 bat.
- What size bat for tee ball?A tee-ball bat is 24 to 26 in long with a 2-1/4 in barrel, at a drop of −14 to −10.5, and carries the USA Baseball tee-ball mark: it is only for use with approved tee balls.