Speed Converter

Type a speed, choose the unit you have and the unit you want, and read the answer straight away, together with the same speed in every other unit. It runs in your browser and nothing is uploaded.

Value

From

0.6213712 mph

1 km/h = 0.6213712 mph

The same amount in every unit

Metres per second: 0.2777778 m/s
Kilometres per hour: 1 km/h
Miles per hour: 0.6213712 mph
Knots: 0.5399568 kn
Feet per second: 0.9113444 ft/s

Calculated instantly in your browser with standard formulas. Double-check anything important. Full disclaimer and terms of use.

Speed conversion factors

Unit	In metres per second	In km/h	In mph
1 m/s	1	3.6	2.2369
1 km/h	0.27778	1	0.62137
1 mph	0.44704	1.609344	1
1 knot	0.51444	1.852	1.15078
1 ft/s	0.3048	1.09728	0.68182

Kilometres per hour and miles per hour: quick reference

km/h	mph	mph	km/h
30 km/h	18.64 mph	20 mph	32.19 km/h
50 km/h	31.07 mph	30 mph	48.28 km/h
80 km/h	49.71 mph	50 mph	80.47 km/h
100 km/h	62.14 mph	60 mph	96.56 km/h
120 km/h	74.56 mph	70 mph	112.65 km/h

Where each unit is used

km/h: road speeds in most countries.
mph: road speeds in the United States and the United Kingdom.
Knots: ships, boats, aircraft and wind speed. One knot is one nautical mile (1,852 m) per hour.
m/s: science, engineering and sport timing, such as sprint speeds.
ft/s: some engineering and ballistics work in the US.

How to convert speed in Excel or Google Sheets

Use =CONVERT(A1,"km/hr","mph") to change km/h in A1 to miles per hour. Other codes include "m/s" and "kn" for knots.

How to use the Speed Converter tool

Type the speed in the Value box.
Choose the unit you are converting from and the unit you want.
Read the answer, or press the arrows to swap the two units.
Look at the table underneath for the same speed in every unit, and copy the answer if you need it.

Frequently asked questions

How do I convert km/h to mph?

Multiply the speed in km/h by 0.621371. For example, 100 km/h is 62.14 mph. A quick estimate is to multiply by 0.6.

How do I convert mph to km/h?

Multiply the speed in mph by 1.609344. For example, 60 mph is 96.56 km/h and 70 mph is 112.65 km/h.

How fast is a knot?

One knot is one nautical mile per hour, which is exactly 1.852 km/h or about 1.15078 mph. Knots are used for ships, aircraft and wind speed.

How do I convert metres per second to km/h?

Multiply by 3.6. For example, 10 m/s is 36 km/h. To go the other way, divide km/h by 3.6.

What are some common speed limits in both units?

50 km/h is about 31 mph, 100 km/h is about 62 mph and 120 km/h is about 75 mph. In the other direction, 30 mph is 48 km/h and 70 mph is about 113 km/h.