Speed, distance and time calculator

Find speed, distance or travel time from the other two, in the units you use.

By the Calcist team · Checked against known answers · Updated October 27, 2026

Private: calculated on your device. Nothing you type is sent anywhere.

Next: Converting the answer to other units? Use the unit converter.

The formula

Speed, distance and time are linked by one formula, which you can rearrange to find any of the three:

Speed = distance ÷ time
Distance = speed × time
Time = distance ÷ speed

The units have to match: miles with hours give miles per hour. This calculator converts everything to meters and seconds first, so you can mix units, like kilometers with mph.

Worked examples

Speed: 120 miles in 2 hours is 120 ÷ 2 = 60 mph.
Distance: 65 mph for 3 hours 30 minutes is 65 × 3.5 = 227.5 miles. Write 30 minutes as 0.5 hours first.
Time: 10 km at 12 km/h takes 10 ÷ 12 = 0.833 hours, which is 50 minutes.

Handy conversions

Unit	Exact value
1 mile	1,609.344 m
1 foot	0.3048 m
1 nautical mile	1,852 m
1 mph	0.44704 m/s
1 km/h	1 ÷ 3.6 m/s
1 knot	1 nautical mile per hour

Limitations

The answer is an average speed. Real trips include stops, traffic and speed changes, so a trip at "60 mph" usually takes longer than distance ÷ 60. To plan a drive, add time for breaks.

Sources

How we checked this

Before every update, this calculator is run in a real browser with these known answers, and it must match all of them:

120 miles in 2 hours = 60 mph ✓
65 mph for 3 h 30 min = 227.5 miles ✓
10 km at 12 km/h takes 50 minutes ✓
A time of zero is refused ✓
26.2 mi in 3 h 59 min 59.6 s: time kept to the tenth, 6.55018 mph ✓

Last checked October 26, 2026. Spotted something wrong? The math is done in your browser with the formula shown on this page, so you can check any result by hand.

Add this calculator to your website (free)

Paste this code into any web page. The calculator works on your page, resizes itself, has no ads and no tracking, and nothing your visitors type is sent anywhere. More about embedding.

<iframe src="https://calcist.com/embed/speed-distance-time-calculator/" title="Speed, distance and time calculator" width="100%" height="640" loading="lazy" style="border:0;max-width:760px"></iframe>
<p style="font:14px/1.4 sans-serif;margin:4px 0 0"><a href="https://calcist.com/speed-distance-time-calculator/">Speed, distance and time calculator</a> by Calcist</p>
<script src="https://calcist.com/embed.js" async></script>

Questions people ask

How do I calculate average speed?

Divide the total distance by the total time. 150 miles in 2 hours 30 minutes is 150 ÷ 2.5 = 60 mph.

How long does it take to drive 100 miles at 60 mph?

100 ÷ 60 = 1.667 hours, which is 1 hour 40 minutes, not counting stops.

How do I convert minutes to hours for the formula?

Divide by 60. 45 minutes is 0.75 hours. Or enter hours, minutes and seconds separately here.

How fast is 100 km/h in mph?

About 62.14 mph. Divide km/h by 1.609344.

Related calculators

Unit converterLength, weight, volume, temperature, speed, data and more.Density calculatorDensity, mass or volume from the other two, with common materials.Basic calculatorA simple four-function calculator with a running tape.Average calculatorMean, median, mode, range and standard deviation.