Your vertical jump is the height you can rise off the floor: your highest touch on a wall minus your standing reach. To dunk on a regulation 10 ft rim, you need a jump that gets your hand about 6 inches over the rim by the usual coaching rule of thumb, so the jump you need depends on your standing reach, not your height.
The calculator below works out three things: your jump height from a wall test or a slow-motion phone video, the jump you need to touch the rim and to dunk, and your peak leg power in watts with its margin of error. Choose what to work out, enter your numbers in feet and inches or centimeters, and press the button.
Vertical Jump Calculator
Example: wall test, 8 ft 0 in standing reach, 10 ft 0 in jump reach, 180 lb
24in
You jumped 24 in, your jump reach minus your standing reach, 6 in short of a dunk on a 10 ft rim.
The equation was fitted on squat jumps from a pause; a normal jump with a dip reads about 2.7% high in it. We give no rating: we could not check a published table of jump norms, so we report the measurement only. Enter your own reach, video or weight above to replace this example.
Peak power
5,344 W
Likely 4,961 to 5,726 W, one standard error either side. Two people need to differ by about 689 to 822 W before the gap is real.
Power per kg
65.5 W/kg
Peak power divided by 81.6 kg body weight.
Jump needed to dunk
30 in
You are 6 in short. Touching the rim takes 24 in.
Measured from your standing reach. Ticks: the jump to touch the rim and the jump to dunk.
| From your reach to the rim | Height | Above your reach |
|---|---|---|
| Your standing reach | 8 ft 0 in | 0 in |
| Rim, 10 ft | 10 ft 0 in | 24 in |
| Top of your jump | 10 ft 0 in | 24 in |
| Dunk lineHand 6 in over the rim, a rule of thumb | 10 ft 6 in | 30 in |
| Next steps |
|---|
| The best exercises to improve your vertical jumpExercises and a sample workout |
| A scientific approach to jumping higherWhat to focus on, and four exercises |
height = 120 in jump reach - 96 in standing reach; power = 60.7 x 61.0 cm + 45.3 x 81.6 kg - 2,055 = 5,344 W. Sources: Sayers 1999 (power); NBA rule book (rim).
The Wall test needs your standing reach and your jump reach. Phone video needs the number of frames you spent in the air and the frame rate you filmed at. Dunk check needs your standing reach only. Add your body weight to get peak power. Nothing you enter leaves your browser.
Table of Contents
- How to Measure Your Vertical Jump With a Wall Test
- How to Measure It From a Slow-Motion Video
- How Much Vertical You Need to Dunk
- Vertical Jump Power: the Sayers Equation
- Why the Calculator Gives No Rating
- Frequently Asked Questions
- Sources
How to Measure Your Vertical Jump With a Wall Test
The wall test, also called the jump-and-reach or Sargent test, is the protocol the power equation below was built on. You need a wall, chalk or a sticky note, and a tape measure.
- Measure your standing reach. Stand side-on to the wall with your feet flat. Reach straight up with the hand nearest the wall and mark the highest point your fingertips touch. Measure from the floor to the mark.
- Jump and touch. Stand side-on again, dip, swing your arms and jump as high as you can, touching the wall at the top with the same hand. Chalk on your fingertips leaves a clear mark.
- Take your best of three. Rest between attempts so each one is a full effort.
- Subtract. Vertical jump = jump reach minus standing reach.
Worked Example
A 180 lb player has a standing reach of 8 ft 0 in (96 in) and touches 10 ft 0 in (120 in) at the top of his jump. His vertical jump is 120 minus 96 = 24 in. His fingertips reach the rim, and he needs 6 in more to dunk.
How to Measure It From a Slow-Motion Video
A phone in slow motion can time how long you stay in the air, and flight time gives jump height through a formula from Bosco and colleagues (1983):
height = 9.81 × flight time² ÷ 8
Your body rises for half the flight time and falls for the other half, so the time in the air fixes how fast you left the floor and how high you went. In a 2015 study, an iPhone app that times jumps this way matched a lab force platform almost exactly in 20 men doing 100 jumps (agreement score 0.997 out of 1, average difference 1.1 cm).
How to Film and Count Frames
- Film side-on at your phone’s highest slow-motion setting, with the phone on something steady and your feet in the frame.
- Find the take-off frame: the first frame with both feet off the ground.
- Find the landing frame: the first frame with a foot back on the ground.
- Count the frames between them and enter that number with your frame rate.
Land with your legs as straight as they were at take-off. Tucking your knees keeps you in the air longer and adds height you did not jump.
Worked Example
You film at 240 frames per second and count 132 frames in the air. Flight time is 132 ÷ 240 = 0.55 s, and 9.81 × 0.55² ÷ 8 = 0.371 m, or 14.6 in. One frame either way changes that by about 0.2 in. At 30 frames per second the same miscount costs about 1.8 in, so use the highest frame rate your phone has. The calculator shows this one-frame error for your own video.
The Video and the Wall Test Measure Different Things
Flight time measures how far your body rose. The wall test measures how high your hand reached, which adds the stretch of your shoulder and arm at the top. In a 2018 study of 135 adults who did both at the same time, the wall test averaged 52 cm and the video method 43 cm. Compare a video result with other video results, and a wall result with other wall results.
How Much Vertical You Need to Dunk
The NBA rule book puts the top of the rim 10 ft (3.05 m) above the floor. The jump you need is the gap between your standing reach and the rim:
- To touch the rim: 120 in minus your standing reach in inches.
- To dunk: add about 6 in, so your hand gets the ball over the rim.
The 6 in is a coaching rule of thumb: we found no study that measures it. The calculator labels it as an assumption, and the touch-the-rim number carries no assumption at all.
A player with a 7 ft 6 in (90 in) standing reach needs a 30 in jump to touch the rim and about 36 in to dunk. A player with an 8 ft 6 in (102 in) reach needs 18 in and about 24 in. Choose Dunk check in the calculator for your own reach, or enter a wall test or video with your standing reach to see how far your jump falls short of the rim or clears it.
Vertical Jump Power: the Sayers Equation
Add your body weight and the calculator estimates peak leg power with the equation Sayers and colleagues published in 1999, fitted on force platform measurements of 108 college-age men and women, athletes and non-athletes:
Peak power (W) = 60.7 × jump height (cm) + 45.3 × body mass (kg) − 2,055
The 180 lb (81.6 kg) player who jumped 24 in (61.0 cm) works out at 60.7 × 61.0 + 45.3 × 81.6 − 2,055 = 5,344 W, or 65.5 W per kg of body weight.
How Much to Trust the Watts
- Error band: Sayers and colleagues tested the equation by predicting each person from everyone else’s data. Its standard error that way is 382 W, so the calculator shows a range of one standard error either side. For the example player that is 4,961 to 5,726 W.
- Comparing two people: Tessier and colleagues (2013) checked the equation against force platform readings and found two people’s estimates need to differ by about 690 to 820 W before you can say one has more power.
- Jump style: Sayers fitted the equation on squat jumps, started from a pause with the knees bent to about 90 degrees. A normal jump with a quick dip reads about 2.7% high in it. Tell the calculator which one you did.
- Video heights: the equation came from wall test heights. A video height usually reads lower, so the power from it likely reads low too.
Use the jump height to track your own progress. It is the measurement you took, and Tessier’s team found jump tests still track jump height well even though the power estimates carry wide errors.
Why the Calculator Gives No Rating
The calculator does not tell you whether your jump is good, average or poor. Ratings need a table of results from a large group of people by age and sex, and the published tables we found are not available to check, so we report your measurement and leave the grading out.
Frequently Asked Questions
How do I calculate my vertical jump?
Subtract your standing reach from the highest point you touch when you jump. With a slow-motion video, multiply 9.81 by your flight time in seconds squared and divide by 8 to get the height in meters.
How much vertical do I need to dunk?
Take your standing reach away from 10 ft (120 in) for the jump that touches the rim, then add about 6 in to dunk. Your standing reach decides the answer, so two players of the same height can need different jumps.
How much vertical do I need to dunk at 5 ft 10 in?
Your standing reach settles it, and two people of the same height can differ in arm length. Measure your reach against a wall and use the Dunk check above. Each inch of extra reach takes an inch off the jump you need.
Can I measure my vertical jump with my phone?
Yes. Film the jump side-on in slow motion, count the frames from take-off to landing, and enter the count and frame rate in the Phone video mode. At 240 frames per second, one miscounted frame moves the result by about 0.2 in.
What is the formula for vertical jump power?
The calculator uses the Sayers equation: peak power in watts = 60.7 × jump height in cm + 45.3 × body mass in kg − 2,055. Its standard error is 382 W, the figure the paper gives when each person is predicted from everyone else’s data.
Is a 28 inch vertical good?
The calculator gives no rating, because we could not check a published table of norms by age and sex. It does tell you what 28 in means on a basketball court: with an 8 ft standing reach, a 28 in jump clears the rim by 4 in and leaves you about 2 in short of a dunk.
How can I jump higher?
Our guides cover the training: the best exercises to improve your vertical jump and a scientific approach to jumping higher. Retest with the same method every few weeks to see the change.
Sources
- Sayers SP, Harackiewicz DV, Harman EA, Frykman PN, Rosenstein MT. Cross-validation of three jump power equations. Med Sci Sports Exerc. 1999;31(4):572-577. doi:10.1097/00005768-199904000-00013 (PMID 10211854).
- Tessier JF, Basset FA, Simoneau M, Teasdale N. Lower-limb power cannot be estimated accurately from vertical jump tests. J Hum Kinet. 2013;38:5-13. doi:10.2478/hukin-2013-0040 (PMID 24235979).
- Bosco C, Luhtanen P, Komi PV. A simple method for measurement of mechanical power in jumping. Eur J Appl Physiol Occup Physiol. 1983;50(2):273-282. doi:10.1007/BF00422166 (PMID 6681758).
- Balsalobre-Fernández C, Glaister M, Lockey RA. The validity and reliability of an iPhone app for measuring vertical jump performance. J Sports Sci. 2015;33(15):1574-1579. doi:10.1080/02640414.2014.996184 (PMID 25555023).
- Yingling VR, Castro DA, Duong JT, Malpartida FJ, Usher JR, O J. The reliability of vertical jump tests between the Vertec and My Jump phone application. PeerJ. 2018;6:e4669. doi:10.7717/peerj.4669 (PMID 29692955).
- National Basketball Association. Official Rules, Rule No. 1: Court Dimensions, Equipment. official.nba.com.
