# Dunk Calculator (Vertical Jump to Dunk)

URL: https://speedycalculator.com/calculators/sports/dunk/
Last updated: 2026-10-30

> The dunk calculator finds the vertical leap you need to dunk a basketball on a hoop of any height from your standing reach and the ball-clearance allowance, plus the jump energy, take-off speed and hang time.

## Inputs

- Hoop
- Hoop height (ft, m, in, yd, cm)
- Body mass (kg, lb)
- Standing reach (ft, cm, in, m)
- Ball clearance above the rim (in, cm)

## Results

- Minimum vertical leap
- Jumping energy
- Take-off speed
- Hang time

## Formula

```
Vertical leap = hoop height − standing reach + clearance,  E = m·g·h,  v = √(2gh),  hang time = √(8h/g)
```

## Explanation

Dunking takes reaching a few inches above the rim with the ball in hand. Your standing reach – how high you can touch flat-footed – and the hoop height decide how much vertical leap you need.

### How to use the Dunk Calculator

- **Hoop**
- **Hoop height**
- **Body mass**
- **Standing reach**
- **Ball clearance above the rim**

Results update as you type, every field has its own unit menu, and everything is calculated in your browser.

### How it works

Choose the hoop (or enter its height), enter your body mass, standing reach and the extra height needed to get the ball over the rim (about 15 cm / 6 in with a palm grip).

### Tips

- Use totals, not per-game averages, for percentages.
- Advanced stats like eFG% and TS% credit three-pointers and free throws properly.
- Compare a player's numbers with league averages.
- Everything runs in your browser.

### Common mistakes to avoid

- Counting free throws as field goals.
- Mixing per-game and season totals.
- Judging shooters from very few attempts.

### Inputs explained

FieldWhat to enterHoopChoose one: Standard 10 ft (3.05 m), 9 ft (grades 5–6), 8 ft (grades 3–4), 7 ft (grade 2 and under) …Hoop heightUnits: ft, m, in, yd, cmBody massUnits: kg, lbStanding reachUnits: ft, cm, in, mBall clearance above the rimUnits: in, cm

### What each result means

- **Minimum vertical leap** = max(0, [H] - [Standing reach] + [Ball clearance above the rim])
- **Jumping energy** = [Body mass]×9.80665×max(0, [H] - [Standing reach] + [Ball clearance above the rim])
- **Take-off speed** = sqrt(2×9.80665×max(0, [H] - [Standing reach] + [Ball clearance above the rim]))
- **Hang time** = sqrt(8×max(0, [H] - [Standing reach] + [Ball clearance above the rim])÷9.80665)

### Example values

How the main result changes when **Hoop height** changes and everything else stays at the example values above:

Hoop height (ft)Minimum vertical leap (in)5307.530103012.53015302030

## Worked example

Inputs — Hoop: Standard 10 ft (3.05 m); Body mass: 80 kg; Standing reach: 8 ft; Ball clearance above the rim: 6 in.

Results — **Minimum vertical leap = 30 in**; Jumping energy = 597.8134 J; Take-off speed = 13.92 km/h; Hang time = 0.7884 s.

## Key terms

- **Vertical leap**: Height gained from a standing or running jump.

## FAQ

**How high must I jump to dunk?**
Typically 50–75 cm (20–30 in) for average-height adults.

**What is standing reach?**
The highest point you can touch with one arm, feet flat.

**Does a bigger hand help?**
Yes – palming the ball needs less clearance.

**What is a typical vertical jump?**
About 40–60 cm for active adults; elite athletes exceed 90 cm.


## Sources

- [Basketball Reference – Glossary](https://www.basketball-reference.com/about/glossary.html)
- [NBA – Draft combine measurements](https://www.nba.com/stats/draft/combine)