MotionLab

Velocity Calculator

The most basic motion formula — distance divided by time.

Distance (m)

Time (s)

Velocity (m/s)

v = d / t

What you entered

Distance (m): 100Time (s): 10

1
v = d ÷ t
100 ÷ 10= 10 m/s

Result

Velocity (m/s): 10

Covering 100m in 10s gives a velocity of 10 m/s.

Velocity from distance and time

Velocity is distance divided by time. These are average velocities over the whole interval.

Distance (m)	Time (s)	Velocity (m/s)	Equivalent
5	1	5.000	Brisk jog
100	10	10.000	Sprint pace
400	45	8.889	400 m in 45 s
1000	50	20.000	72 km/h
42195	7200	5.860	Marathon in 2 hours

Multiply metres per second by 3.6 to get kilometres per hour, which is the conversion worth memorising: 10 m/s is 36 km/h. The marathon row is close to the world record pace and works out at 5.86 m/s, or 21.1 km/h sustained for two hours. Note this is average velocity over the interval - it says nothing about the fastest or slowest moment within it. Strictly, velocity is a vector with direction, while speed is its magnitude; over a closed loop the average velocity is zero even though the speed was not.

Velocity vs. speed

Speed is just how fast something moves; velocity also includes direction. This calculator computes the magnitude only — for a full vector answer you'd also need to track direction separately.

Average vs. instantaneous

This gives average velocity over the full distance and time — an object's instantaneous velocity at any single moment can be higher or lower than this average if its speed varies along the way.

Frequently asked questions

A cyclist covers 90 km in 3 hours. What's their average velocity?

v = d/t = 90/3 = 30 km/h (about 8.33 m/s). This is the average — they likely went faster downhill and slower uphill, but it all averages out.

How is velocity different from speed?

Speed is a scalar (magnitude only), while velocity is a vector (magnitude + direction). This calculator gives the magnitude. An object moving in a circle at constant speed has changing velocity because its direction keeps changing — that's what causes centripetal acceleration. See the centripetal force calculator.

What's the difference between this and the acceleration calculator?

This calculator finds constant velocity from distance and time. The acceleration calculator handles situations where velocity is changing — if your speed goes from 0 to 30 m/s, that's an acceleration problem, not a constant-velocity problem.