Dunk Calculator

Dunking comes down to one number: your max reach versus the 10-foot rim. Enter your height and vertical jump, and we'll tell you whether you can throw it down — and exactly how many more inches you need if you can't yet. Runs entirely in your browser.

Height — feet

Height — inches

Vertical jump (inches)

Standing reach, measured (inches) optional — overrides the estimate

Estimates only. Standing reach is estimated from height (roughly 1.33× height, the typical ratio) unless you enter a measured value. To dunk you need your hand about 6 inches above the 10-foot rim so the ball clears it — individual arm length, palm size and jumping technique matter too.

Frequently Asked Questions

How tall do you need to be to dunk?

It's not really about height — it's about standing reach plus vertical jump. A 6'0" player with a 30-inch vertical and an 8'0" standing reach touches 10'6" at peak, which is enough to dunk. Plenty of players under 6 feet dunk with 34+ inch verticals, while some 6'5" players can't because their reach is short or their jump is low.

What vertical jump do I need to dunk?

You need your hand roughly 6 inches above the 10-foot rim (about 10'6" of reach) to get the ball over and down. So: required vertical = 126 inches − your standing reach. With a typical 7'8" standing reach, that's about 34 inches; with an 8'4" reach, only about 26 inches.

How do you measure standing reach?

Stand flat-footed next to a wall, reach one arm straight up as high as you can, and mark the highest point your fingertips touch. Measure from the floor to the mark. That's the number to enter above — it replaces the height-based estimate and makes the result much more accurate.

Can I dunk with a 24-inch vertical?

Probably not unless you're tall. A 24-inch vertical adds 2 feet to your standing reach — you'd need about an 8'6" standing reach to touch 10'6", which usually means being around 6'5" with long arms. Most dunkers need 28–34 inches of vertical. The calculator above shows your exact gap.

What's a good vertical jump?

For reference: the average untrained adult male vertical is around 16–20 inches and untrained adult female around 12–16 inches. High-school varsity basketball players often jump 24–28 inches, college players 28–34, and NBA draft prospects commonly test 34–40+ inches at the combine.

How can I increase my vertical jump?

Squat strength relative to body weight is the biggest driver — back squats, trap-bar deadlifts and Bulgarian split squats build the base. Add plyometrics (box jumps, depth jumps, bounding) 1–2 times a week, keep sprinting in the mix, and don't skip calf and ankle stiffness work. Most athletes add 4–8 inches in a focused 12-week block.