About
Built for the rim
A free calculator that turns your height, reach and jump into a clear number to work toward.
Why it exists
Most people guess whether they can dunk. Jump2Dunk replaces the guess with arithmetic: your standing reach, your current vertical and the rim height you play on.
It keeps touching the rim and dunking apart, because they need different amounts of height above the rim.
What we stand for
Honest numbers
Results are estimates. We never promise a dunk.
Private
Everything runs in your browser. Your numbers stay with you.
Simple
No sign-up, no ads in the way, and nothing to install.
How the numbers are worked out
The calculator subtracts your standing reach from the rim height to get the jump that puts your fingertips on the rim, then adds a margin for the dunk you have in mind. Subtract your current vertical and what is left is your gap. The margins are planning choices made for this tool, not official standards, and the maths is spelled out step by step in how the calculation works.
Height-based figures lean on a common rule of thumb that standing reach is about 1.31 × height. It is an average, so measuring your own reach always gives a better answer.
What it can’t do
Reach arithmetic can’t measure timing, technique, ball control or hand size. Treat the result as a planning target, and build jump volume gradually.
Try the calculatorWhere to start
New here? Measure your reach with the standing reach calculator and your jump with the vertical jump calculator, then compare them in the dunk calculator. The guides cover the vertical needed to dunk by height, the different dunk types and whether short players can dunk. Questions or corrections are welcome on the contact page.