Dunk Calculator
Find out the vertical jump you need to dunk. Enter your standing reach in inches, the rim height (10 ft standard), and how far your hand must clear the rim, and get the vertical needed to dunk and to touch the rim.
Example: with Standing reach (inches) 96 · Rim height (feet) 10 · Hand clearance above rim (inches) 6 → Vertical needed to dunk: 30.0 in vertical needed.
- Vertical to touch the rim24.0 in vertical needed
- How big a hop that isStrong vertical — real hops
Computed by the calculator below using its default values. Change any input to see your own numbers.
To dunk you need your hand roughly six inches above a 10-ft rim. Vertical needed = rim height + clearance - your standing reach.
The math behind the dunk
Dunking is a reach problem before it is a jumping problem. What matters is how high your hand gets, which is your standing reach plus your vertical jump. To throw it down cleanly, your hand needs to clear the rim by about six inches so the ball goes over. So the vertical you need equals the rim height (120 inches for a regulation 10-foot rim) plus that clearance, minus your standing reach.
That is why two players of the same height can have very different dunking requirements: longer arms mean a higher standing reach and a smaller jump to make up. Measure your real standing reach - arm fully up, feet flat - rather than guessing from height.
Is your target realistic?
A vertical under about 16 inches is very trainable for most healthy athletes. The mid-20s in inches is a solidly athletic hop, the low 30s is strong, and 40-plus inches is elite, the territory of pro guards and combine standouts. If the number the tool shows is daunting, remember you can shrink it by improving standing reach through jump technique and by chasing the touch-the-rim milestone first. Lowering the rim or using a smaller ball are common stepping stones for younger players.
How it’s calculated
Vertical needed to dunk = rim height (feet x 12) + hand clearance - standing reach, all in inches. Vertical to touch the rim = rim height - standing reach. A regulation rim is 10 ft (120 in); the default 6 in clearance lets the ball pass over the rim.
Uses the standing reach you enter, not an estimate from height, and ignores how far you can extend your arm at the peak of the jump. Measure your true standing reach for the most accurate target.
Vertical needed to dunk by height (10 ft rim)
| Height | Est. standing reach | Vertical to dunk |
|---|---|---|
| 5 ft 8 in | ~7 ft 6 in | ~36 in |
| 5 ft 10 in | ~7 ft 9 in | ~33 in |
| 6 ft 0 in | ~8 ft 0 in | ~30 in |
| 6 ft 2 in | ~8 ft 2 in | ~28 in |
| 6 ft 4 in | ~8 ft 5 in | ~25 in |
| 6 ft 6 in | ~8 ft 8 in | ~22 in |
Standing reach estimated as about 1.33 x height; dunk assumes a hand ~6 in above a 10-ft rim. Measure your real reach for accuracy.
Common mistakes
- Guessing standing reach from height - arm length varies a lot between people.
- Forgetting the clearance; your hand must get above the rim, not just to it.
- Using a lowered rim height but expecting to dunk on a regulation 10-ft goal.
- Comparing your vertical to a running-jump number when your reach was measured standing.
Frequently asked questions
How do you calculate the vertical needed to dunk?
Take the rim height plus a hand clearance (about 6 inches) and subtract your standing reach. On a 10-foot rim that is 120 + 6 - reach, all in inches.
What is standing reach?
How high you can touch with your feet flat on the floor and one arm stretched straight up. It combines your height and arm length and is the starting point your jump adds to.
Do I really need to clear the rim by 6 inches?
You need your hand high enough to put the ball over the rim, which is a few inches above it. Six inches is a safe, clean-dunk default; a hard one-hander can get by with a little less.
What vertical do most people need to dunk?
For an average-height adult around 6 feet with typical arm length, roughly a 30-inch vertical on a regulation rim. Taller or longer-armed players need less.
How can I make dunking easier?
Improve your standing reach and jump technique, start with touching the rim, and build lower-body power. Younger players often practice on a lowered rim or with a smaller ball first.