40 Yard Dash Calculator
Convert your 40-yard dash time into speed in mph, estimated 10- and 20-yard splits, and average velocity. A staple combine speed metric.
By Jonas Lindemann · Updated · How we build our calculators
Electronic (laser) time, as at the NFL Combine
20.9mph
Estimated top speed (33.6 km/h)
17.8mph
Average speed (28.6 km/h)
Excellent
1.60s
10-yard split
2.63s
20-yard split
1.97s
Last 20 yards
Average speed is 40 yards divided by your time. Splits and top speed use a sprint acceleration model fitted to NFL combine splits: a 4.6 s runner covers the first 10 yards in about 1.6 s, then reaches top speed near the finish.
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Calculation Method
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 average and estimated top speed in miles per hour and km/h, and estimates your 10- and 20-yard splits with a sprint acceleration model 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:
Speed (mph) = Speed(m/s) × 2.23694
Speed (km/h) = Speed(m/s) × 3.6
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 top speed: about 20.9 mph (9.3 m/s)
- Estimated 10-yard split: about 1.60 s
- Estimated 20-yard split: about 2.63 s
How the Splits Are Estimated
Sprinters start from zero and accelerate for most of the 40, so the first 10 yards take far longer than a quarter of the total time. The calculator uses the exponential acceleration model from sprint research:
d(t) = vmax × (t − τ × (1 − e−t/τ))
The time constant τ = 0.68 s is fitted to typical electronic NFL combine splits, where the 10-yard split is about 34–36% and the 20-yard split about 57–60% of the 40 time. Your 40 time then sets the top speed vmax, and each split is the time at which d(t) reaches 10 or 20 yards. Top speed comes out about 1.18 times the average speed.
| 40 time | 10-yard | 20-yard | Average | Top speed |
|---|---|---|---|---|
| 4.30 s | 1.51 s | 2.47 s | 19.0 mph | 22.6 mph |
| 4.50 s | 1.57 s | 2.58 s | 18.2 mph | 21.4 mph |
| 4.60 s | 1.60 s | 2.63 s | 17.8 mph | 20.9 mph |
| 4.80 s | 1.65 s | 2.73 s | 17.0 mph | 19.9 mph |
| 5.00 s | 1.70 s | 2.83 s | 16.4 mph | 18.9 mph |
| 5.50 s | 1.84 s | 3.08 s | 14.9 mph | 17.0 mph |
40-Yard Dash Benchmarks
| Time | Level |
|---|---|
| 4.40 or faster | Elite (combine top tier) |
| 4.41 – 4.60 | Excellent |
| 4.61 – 4.80 | Above average |
| 4.81 – 5.20 | Average |
| Slower than 5.20 | Below average |
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. Tick "hand-timed" in the calculator to add the common 0.24-second correction.
Note: This calculator is for educational use. Splits and top speed come from a standard acceleration model and are estimates; individual acceleration profiles vary.
Frequently Asked Questions
Covering 40 yards (36.58 m) in 4.5 seconds is an average speed of about 18.2 mph (29.3 km/h). Because you accelerate from a standstill, top speed near the finish is higher, about 21.4 mph (34.4 km/h).
Elite NFL skill players run 4.3-4.5 seconds; 4.5-4.7 is fast for most athletes, and under 5.0 is solid for larger players. Times vary widely by position and body size.
No. The calculator estimates splits from your full 40 time with an exponential acceleration model fitted to NFL combine splits (a 4.5 s 40 gives about a 1.57 s 10-yard and 2.58 s 20-yard split). Real splits depend on your start and acceleration, so treat them as approximations.