Dunk Calculator: Can You Dunk?

Free dunk calculator from height, standing reach and vertical jump. See how close you are to a regulation 10 ft rim and what to train next.

Use this dunk calculator with your height, standing reach and vertical jump to estimate whether you can reach a regulation 10 ft rim with margin for the ball, and how many inches you still need.

This dunk calculator answers a simple question coaches and players ask: with your height, standing reach and vertical jump, can you get high enough to dunk on a regulation rim? It uses a standard rim height of 10 feet (120 inches) under NFHS, NCAA, FIBA and NBA rules, plus a small clearance margin so the ball can finish over the metal, not just your fingertips at rim level.

The math is only a ceiling check. Timing, ball control, approach angle and live defenders still decide whether a dunk happens in a game.

Dunk Calculator

Units Inches Centimeters

Height (barefoot) Standing reach (flat feet, reach up) Vertical jump (highest touch minus standing reach)

Enter your height, standing reach and vertical jump to see a result.

The regulation basket sits 10 feet above the floor at every standard level. Your standing reach plus vertical jump must exceed that height with room for the ball.

How the Dunk Calculator Works

The tool adds your standing reach and vertical jump to estimate peak reach at the top of your jump. It compares that number to a 10 ft rim (120 inches) plus about 6 inches of clearance so the ball can finish above the rim, not just kiss the front of the iron.

That clearance number is a teaching estimate, not a combine measurement. Longer hands, better timing on the gather or a two-hand finish can change what you need in real life.

How to Measure Standing Reach and Vertical Jump

Standing reach: shoes off, feet flat, reach straight up with one hand and mark the highest fingertip. Many coaches use a wall mark or a Vertec-style vanes without jumping.
Vertical jump: the gain from standing reach to your highest controlled touch on a jump. If you use a running approach in games, test both standing and approach jumps and enter the number that matches how you plan to dunk.
Height: barefoot height helps catch typos when reach looks impossible for a player's size.

The approach lane matters for running dunks. Players who need extra inches often gain them with a clean gather in the lane, not from standing under the rim.

Jump training progressions for players who are close are on basketball vertical jump training. Court and rim specs are on basketball court dimensions.

What to Train If You Are Close

Finishes at the rim start with a target above the front of the iron. Players who only reach rim height often need a two-hand finish or a soft touch on the back rim at first.

Players who miss by a few inches usually need a blend of lower-body power, approach footwork and finish confidence, not just more max jump tests in isolation. Coaches often pair rim-touch drills with strength work and short approach reps before they ask for live dunk attempts in practice.

Link back to the calculator after a training block and update the vertical number. Even a 1 to 2 inch gain can move a player from "short" to "possible" on paper. Plyometric progressions are on basketball plyometric exercises, and leg strength work is on strength training for basketball.

Questions Coaches Ask About Dunking

How tall do you have to be to dunk?

There is no single height. Standing reach and vertical jump matter more than listed height. Short players with long reach and a big vertical can dunk; tall players with poor jump numbers may not.

What rim height does the calculator use?

10 feet (120 inches), the regulation goal height in NFHS, NCAA, FIBA and NBA play.

Does running start count?

Enter the vertical that matches your test. A running approach usually adds inches compared with a standstill jump, so label what you measured before you trust the result.

Is this calculator medical or scouting advice?

No. It is a rough physics check. Clear hard training with a qualified coach before you add heavy jump volume.

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