Velocity Calculator (Average Velocity = Distance ÷ Time)
Average velocity from distance and time, in m/s, km/h and mph, with the working.
Inputs
- Working
- 100 m ÷ 10 s = 10 m/s
- In km/h and mph
- 36.00 km/h = 22.37 mph
- Time for 1 km at this speed
- 100.0 s
- Distance in 1 minute
- 600.0 m
Use this calculator on your own site
Free embed
- Two lines of HTML, unlimited views
- Shows a small CalculateEveryday bar, with a credit link under the calculator
What each Velocity input means
- Distance
- How far the object moved, in metres. For straight-line motion it is both the distance and the displacement; for a round trip, enter the path length if you want the average speed. A distance in km × 1,000 is metres.
- Time
- How long it took, in seconds. Minutes × 60 and hours × 3,600 convert it; the page refuses zero or negative times.
Velocity formula
average velocity = displacement ÷ time · average speed = distance ÷ time · 1 m/s = 3.6 km/h = 2.237 mph
Average velocity is how far something moved divided by how long it took. Strictly, velocity uses displacement — the straight-line change in position, with a direction — while speed uses the distance travelled along the path; for motion in a straight line the two are the same, which is what this page assumes. The result is in metres per second, the SI unit, and the page converts it to km/h and mph and shows what that pace means over a kilometre and over a minute. Instantaneous velocity, what a speedometer reads at one moment, is the same ratio taken over a vanishingly short interval; the average is what you can compute from a stopwatch and a tape.
Velocity worked example
100 metres in 10 seconds: 100 ÷ 10 = 10 m/s, which is 36 km/h or 22.4 mph. At that pace a kilometre takes 100 seconds and a minute covers 600 m. A marathon runner at 5:00 per km is 3.33 m/s; a car at 100 km/h is 27.8 m/s.
More Velocity examples
A marathon, 42,195 m, in exactly 2 hours (7,200 s): 42,195 ÷ 7,200 = 5.8604 m/s, which is 21.10 km/h or 13.11 mph — a kilometre every 170.6 seconds, just under 2 minutes 51.
One lap of a 400 m track in 50 seconds: 400 ÷ 50 = 8 m/s, or 28.8 km/h. Back on the starting line, the runner's displacement is zero, so the strict average velocity is 0 while the average speed is 8 m/s.
Where the Velocity calculator can give the wrong answer
- Average velocity says nothing about the speed at any moment. A car that sits in traffic and then races still averages the same figure as one that cruised.
- Displacement, not path length, is the strict definition. A round trip has zero displacement and zero average velocity, though a positive average speed; enter the distance travelled if speed is what you want.
- Units must match: metres with seconds. A distance in km and a time in minutes needs converting first — or use the speed converter for the final number.
- Very short times measured by hand carry reaction-time error of a few tenths of a second, which matters for a sprint and not for a road trip.
- Time is a positive quantity here; the page refuses zero and negative times.
Spotted a mistake? Tell us
Velocity reference table
| m/s | km/h | mph |
|---|---|---|
| 1 | 3.6 | 2.2 |
| 5 | 18 | 11.2 |
| 10 | 36 | 22.4 |
| 20 | 72 | 44.7 |
| 27.78 | 100 | 62.1 |
| 30 | 108 | 67.1 |
| 50 | 180 | 111.8 |
| 100 | 360 | 223.7 |
Velocity FAQ
- Divide the displacement (or distance, for straight-line motion) by the time taken. 150 m in 30 s is 5 m/s. Multiply by 3.6 for km/h (18 km/h) or 2.237 for mph (11.2 mph). Enter distance and time above.
- Speed is distance ÷ time and has no direction; velocity is displacement ÷ time and does. Walking 100 m east then 100 m back in 100 s is a speed of 2 m/s and a velocity of 0.
- Multiply by 3.6, because there are 3,600 seconds in an hour and 1,000 metres in a kilometre. 10 m/s = 36 km/h; 27.8 m/s = 100 km/h. For mph, multiply by 2.237.
- Rearrange: time = distance ÷ velocity and distance = velocity × time. 400 m at 8 m/s takes 50 s; 8 m/s for 2 minutes covers 960 m. The drive-time calculator on this site does the distance ÷ speed version in km/h and mph.
- Divide the total distance by the total time — not the average of the two speeds. 60 km at 60 km/h then 60 km at 30 km/h takes 1 + 2 = 3 hours, so the average is 120 ÷ 3 = 40 km/h, not 45.
- Multiply by 0.44704, exactly, since a mile is 1,609.344 m and an hour is 3,600 s: 60 mph is 26.82 m/s.