mph to km/h converter

How the mph to km/h converter works

Type a speed in miles per hour and read the kilometers per hour next to it. The round button swaps the units to go from km/h to mph, and the list below adds knots, meters per second and the minutes-per-kilometer pace. A value such as 60 works as is, and so does a sum.

Examples: 30 mph is 48.3 km/h, 55 mph is 88.5 km/h, 65 mph is 104.6 km/h and 75 mph is 120.7 km/h. In the other direction, 50 km/h is 31.07 mph, 90 km/h is 55.9 mph, 120 km/h is 74.6 mph and 130 km/h is 80.8 mph. Type any of them in the mph to km/h converter to check.

One mile is exactly 1.609344 kilometers, so 1 mph is 1.609344 km/h (NIST). To convert mph to km/h you multiply by 1.609344: 60 mph is 96.56 km/h and 100 km/h is 62.14 mph. The mph to km/h converter keeps every decimal. Note that mph to kph is the same conversion, kph being another way to write km/h.

Speed limits, speedometers and knots

In the US and the UK, road signs are in miles per hour, while Canada, Mexico and most of Europe post their speed limit in km/h. A 30 mph limit is 48 km/h, 65 mph is 105 km/h, and a 50 km/h limit is 31 mph. Many cars sold in the US carry a smaller km/h scale on the speedometer, which helps when you cross a border.

Mental shortcut: multiply miles per hour by 1.6, or add half and a tenth. 70 mph is about 112 km/h. In the other direction, multiply km/h by 0.6. For a figure that goes in a trip plan or a car listing, the mph to km/h converter is the safer bet.

Weather and sport use the same units. A 20 mph wind is 32 km/h, and a cyclist or a runner at 10 km/h is going 6.2 mph. Forecasts in the US give wind in mph and most other countries use km/h, so the mph to km/h converter comes in handy whenever you read a forecast from abroad.

At sea and in the air, speed is in knots, one nautical mile per hour, which is 1.852 km/h. For distances, see the km to miles converter.