How high do you need to jump to dunk? Do the math

To dunk you have to get your wrist about 15 cm above the rim, so around 3.20 m off the ground. Touching the hoop isn't enough: you need room to bring the ball over the edge and push it down.

So how many centimeters of jump you need comes down to one thing: your standing reach. And you can work it out in two minutes.

The math, step by step

1. Measure your standing reach. Standing up, feet flat on the floor, stretch one arm as high as you can and have someone mark the point your fingertips reach. That's your standing reach. For most people it's about 1.30 times their height, but it varies a lot with arm length, so actually measure it instead of estimating.
2. Subtract your reach from 3.20 m (the 3.05 m rim plus the margin you need to get the ball through).
3. What's left is the vertical you need.

A few real examples

• Reach 2.20 m → you need about 100 cm of jump. That's elite-athlete territory.
• Reach 2.40 m → you need about 80 cm. Hard, but reachable with years of serious work.
• Reach 2.55 m → you need about 65 cm. Within range for plenty of trained athletes.
• Reach 2.70 m → you need about 50 cm. With a good program you'll get there.

This is why two players the same height can have wildly different targets: long arms are a head start no amount of training closes.

Three things the math doesn't tell you

Your hand matters. If you can't palm the ball one-handed, you need more margin above the rim, because you have to get there with two hands — and the two-handed move sits lower. A lot of people solve ball control before they solve centimeters.

A running jump is higher than a standing one. Every serious dunk number refers to the approach jump: if you're measuring standing, you're using the wrong number for this goal.

One foot or two changes everything. Off one foot the ground contact is very short and you need reactivity; off two feet you have more time and strength is what counts. Plenty of people find a 5-8 cm gap between the two, and it's worth betting on whichever one works better for you.

Now the missing number: how high you jump today

The math above tells you what you need. To know how far off you are, you need the other half: your current vertical.

With the JHP jump test you get it in two minutes, free: you upload a two-second video of yourself jumping and get your vertical in centimeters, calculated from flight time. No app needed, the analysis runs in the browser and the video never leaves your phone.

➡️ Measure your vertical, free

Do the subtraction and your goal is written in centimeters, instead of "I'd like to dunk".

How many centimeters can you actually gain?

Here's the uncomfortable part: there is no single number that works for everyone, and anyone promising you one is selling air. It depends on how trained you are right now, how much strength you already have in the bank, your age, your consistency, and how much headroom your nervous system still has.

Someone who has never trained explosive strength has the biggest margin ahead of them. Someone who has been training for five years has to work much harder for much less. The only serious way to answer is to measure, train for four weeks, measure again — and at that point you know your rate of improvement, which is the only number that counts.

How those centimeters get built

You don't train the jump by jumping more: you train it with maximal strength, plyometrics, and the way those two get alternated across the week.

The JHP subscription gives you 13 programs with day-by-day plans, video for every exercise and WhatsApp support, at €99/year. For the dunk goal:

• JHP Gym Edition — 16 weeks in the weight room on maximal strength and power, the base without which nothing else works (€60)
• Jumping Monster — 14 days of intensive plyometrics, 116 exercises (€40)
• The French Contrast Method — heavy strength alternated with explosive movements in the same session (€90)
• Knee Power — because landing from a dunk costs your knees (€40)
• Basket Advanced — the package built for basketball players (€80)

You might also like: how to raise your vertical to dunk and how high NBA players jump.