Speed Calculator

Work out speed, distance or travel time from the other two using speed = distance ÷ time.

Your result will appear here

Fill in the fields and press Calculate.

Speed, distance and time are bound by one simple relationship: speed = distance ÷ time. Give any two and the third follows — how fast you were going, how far you'll get, or how long a trip will take.

Choose what you're solving for, enter the two values you know, and the answer appears instantly.

How is it calculated?

The speed triangle

Solve forFormula
Speeddistance ÷ time
Distancespeed × time
Timedistance ÷ speed

The units are yours: kilometres and hours give km/h, miles and hours give mph, metres and seconds give m/s. Just keep the distance and time units consistent with the speed unit you want.

Watch the time units

The most common mistake is mixing hours and minutes. A 30-minute trip is 0.5 hours, not 30, when you want km/h. Convert minutes to hours (÷ 60) or seconds to hours (÷ 3600) before entering them, or your speed will be off by a large factor.

Average vs instantaneous speed

This calculator gives *average* speed over the whole trip — total distance divided by total time. It does not capture how fast you were going at any single moment, which is what a speedometer shows. For a journey with stops, the average is always lower than the cruising speed.

Where it helps

Estimating arrival time, checking a pace, converting a run or drive into a speed, or physics homework. For running specifically, a pace calculator expresses the same idea as minutes per kilometre.

Worked example

You drive 150 km and it takes 2 hours: speed = distance ÷ time = 150 ÷ 2 = 75 km/h. Turn it around — at 75 km/h, a 240 km trip takes time = distance ÷ speed = 240 ÷ 75 = 3.2 hours, or 3 hours 12 minutes (0.2 × 60 = 12). Note the average already folds in any traffic and stops within those two hours.

FAQ

How do I calculate speed?+

Divide the distance travelled by the time taken: speed = distance ÷ time. 150 km in 2 hours is 75 km/h. Choose "Speed" mode and enter distance and time.

How do I find travel time?+

Divide the distance by the speed: time = distance ÷ speed. 240 km at 80 km/h takes 3 hours. Make sure the speed and distance use the same distance unit.

What units does this use?+

Any consistent set: km and hours give km/h, miles and hours give mph, metres and seconds give m/s. The tool doesn’t assume a unit — you keep them consistent.

How do I handle minutes?+

Convert to the time unit that matches your speed. For km/h, a 45-minute trip is 45 ÷ 60 = 0.75 hours. Entering 45 instead of 0.75 gives a wildly wrong speed.

Is this average or instantaneous speed?+

It is the average speed over the whole trip: total distance ÷ total time. Instantaneous speed (what a speedometer reads) can be higher or lower at any given moment.