8 miles per hour to kilometers per hour
12.9 km/h
8 mph = 12.9 km/h.
kilometers per hour
12.9km/h
8 mph = 12.9 km/h
The short answer
How many kilometers per hour is 8 miles per hour?
8 mph = 12.9 km/h. 1 miles per hour = 1.609344 kilometers per hour, so the working is 8 × 1.609344 = 12.9.
The working
The factor below is an exact definition rather than a measurement, so nothing is approximated in the arithmetic. The only rounding on this page happens where a number is displayed.
1 miles per hour = 1.609344 kilometers per hour 8 × 1.609344 = 12.9
How much precision do you need?
Each row is the same answer cut at a different number of decimals, with what that choice costs you. Pick the shortest row whose error is smaller than whatever you are measuring with.
| Rounded to | Answer (km/h) | Off by |
|---|---|---|
| Whole number | 13 | +0.12525 |
| 1 decimal | 12.9 | +0.02525 |
| 2 decimals | 12.87 | −0.00475 |
Round trip: take 12.9 km/h back the other way and you land on 8.0157 mph — a drift of 0.0157 mph. That gap is the rounding, not the conversion.
Frequently asked questions
What is 8 miles per hour in kilometers per hour?
8 miles per hour is 12.9 kilometers per hour. 1 miles per hour = 1.609344 kilometers per hour, so the working is 8 × 1.609344 = 12.9.
How accurate is 12.9 km/h?
Rounding to 12.9 km/h and converting straight back gives 8.0157 mph, a drift of 0.0157 mph from the 8 you started with. The factor itself is exact; every bit of that difference comes from the rounding, not the conversion.
Nearby values
Any value at all
MPH to KM/H Converter
Miles per hour to kilometers per hour, with the speed limits you will actually meet.
Open the mph to km/h converter →