40 Yard Dash Calculator

The 40-yard dash is the headline speed test of the NFL Scouting Combine and football tryouts everywhere. A single time captures a player's straight-line burst over a distance that mirrors a deep route or a kick return. This calculator converts your 40 time into an average speed in miles per hour and km/h, and estimates your 10- and 20-yard splits so you can see how your acceleration stacks up.

Converting Time to Speed

Speed is distance over time. Forty yards is 36.576 metres, so:

This gives your average speed across the full 40. Your top speed in the final yards is higher, because you start from a dead stop and accelerate throughout.

Worked Example

A player runs a 4.60-second 40:

• m/s: 36.576 / 4.60 = 7.95 m/s
• mph: 7.95 × 2.23694 = 17.8 mph
• km/h: 7.95 × 3.6 = 28.6 km/h
• Estimated 10-yard split: 4.60 × (10/40) = 1.15 s
• Estimated 20-yard split: 4.60 × (20/40) = 2.30 s

The split estimates assume an even pace. Real sprints accelerate, so a player's actual 10-yard split is slightly slower than the even-pace estimate and the final 10 yards faster.

40-Yard Dash Benchmarks

Hand-Timed vs Electronic

Hand-timed 40s with a stopwatch typically read 0.2–0.3 seconds faster than the laser-timed system used at the official Combine, because a human reacts late to the start. If you compare yourself to combine numbers, make sure you are comparing the same timing method.

Note: This calculator is for educational use. Split estimates assume uniform pacing and are approximations of true acceleration profiles.