Vertical Jump Power Calculator (Sayers Formula)
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/8/2026
Peak power is calculated with 60.7 × jump height (cm) + 45.3 × body mass (kg) − 2055. For a 40 cm jump at 80 kg, estimated power is about 3,997 W.
Explanation
The countermovement vertical jump is one of the most widely used field tests in strength and conditioning to estimate lower-body explosive power, without needing lab equipment (a force plate) that would give a direct measurement. The Sayers formula, published in 1999 after cross-validation against direct force-plate measurements, remains one of the most cited equations for converting a simple jump height and body mass into a peak power estimate in watts. It isn't the only formula available: other older equations (Lewis, Harman) also exist, sometimes giving noticeably different results for the same jump, which makes comparing results across different formulas of limited use — it's always best to compare measurements taken with the same equation over time. Lower-body power estimated this way is a key indicator in strength and conditioning for sports requiring explosive actions (sprinting, jumping, changes of direction), and commonly serves as a benchmark for tracking an athlete's progress through a strength-speed training program. For a one-rep max rather than explosive power, see our 1RM calculator; to compare several estimation formulas for the same indicator, our 1RM formula comparison calculator applies a similar principle to a different indicator.
Example: a 40 cm jump, 80 kg body mass
Inputs
Jump height: 40 cm. Body mass: 80 kg.
Calculation
Power = 60.7 × 40 + 45.3 × 80 − 2055 = 2,428 + 3,624 − 2,055 = 3,997 W.
Result
The estimated peak power for this jump is about 3,997 W.
Frequently asked questions
Why use a formula rather than a direct force-plate measurement?
Because a force plate remains costly lab equipment, not widely accessible outside specialized strength and conditioning centers. The Sayers formula offers a reasonably reliable estimate from two simple measurements (jump height, body mass), obtainable with minimal equipment, making it a practical compromise widely adopted in the field.
Why does the Sayers formula give a different result from the Lewis formula for the same jump?
Because each formula was derived from a different statistical regression on a sample of subjects and force-plate measurements specific to its original study, producing different coefficients. Neither is universally 'more correct' in absolute terms: what matters most is always using the same formula to compare measurements over time, rather than mixing results from several equations.
How do you correctly measure jump height without specialized equipment?
The Sargent method (marking with fingertips, arm extended, the highest point reached at the top of the jump, then measuring the gap from the point reached with the arm extended without jumping) remains accessible without specific equipment, though less precise than a contact mat or force plate. A contact mat on the ground, which measures flight time to derive height, offers intermediate precision at a reasonable cost.