Convert 1 Mile/Hour (mph) to Kilometer/Hour (km/h).

1 Mile/Hour equals 1.609344 Kilometer/Hour. Multiply 1 by 1.609344.

1 Mile/Hour = 1.609344 Kilometer/Hour

Worked example: converting Mile/Hour to Kilometer/Hour

Step 1 — start with the formula. km/h = mph × 1.609344
Step 2 — substitute your figure. 1 mph × 1.609344
Step 3 — read the result. 1 mph = 1.609344 km/h
Step 4 — check it in reverse. mph = km/h × 0.6213711922 returns 1 mph, which matches the figure you started with.

Speed Converter

18 units available

Decimals:

From

To

1.609344

1 mph = 1.609344 km/h

Formula:

km/h = mph × 1.609344

With your value: 1 mph = 1.609344 km/h

How big is that?

Everyday references on a logarithmic scale, all expressed in mile/hour so you can sanity-check the result.

Your value1.00 mph

Walking pace (3.1× your value)3.13 mph

Cycling (12× your value)12.3 mph

Urban speed limit (50 km/h) (31× your value)31.1 mph

Cheetah sprint (65× your value)64.9 mph

Motorway (110 km/h) (68× your value)68.5 mph

Other Mile/Hour to Kilometer/Hour conversions

2 mph to km/h 3 mph to km/h 4 mph to km/h 5 mph to km/h 6 mph to km/h 7 mph to km/h 8 mph to km/h Full Mile/Hour to Kilometer/Hour converter

Mile/Hour to Kilometer/Hour Conversion Table

Mile/Hour (mph)	Kilometer/Hour (km/h)
0.5	0.804672
1	1.609344
2	3.218688
5	8.04672
10	16.09344
15	24.14016
20	32.18688
25	40.2336
50	80.4672
100	160.9344
250	402.336
500	804.672
1000	1,609.344

Kilometer/Hour to Mile/Hour Conversion Table

Kilometer/Hour (km/h)	Mile/Hour (mph)
0.5	0.310686
1	0.621371
2	1.242742
5	3.106856
10	6.213712
15	9.320568
20	12.427424
25	15.53428
50	31.06856
100	62.137119
250	155.342798
500	310.685596
1000	621.371192

Where these values come from

Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.

Mile/Hour (mph)

Speed

Exact conversion

Derived quantity: a defined length divided by a defined time interval.

Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)

Bureau International des Poids et Mesures · Reviewed 2026-07-01

Kilometer/Hour (km/h)

Speed

Exact conversion

Derived quantity: a defined length divided by a defined time interval.

Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)

Bureau International des Poids et Mesures · Reviewed 2026-07-01

Standards and context behind Mile/Hour to Kilometer/Hour

Vienna Convention on Road Signs: Frames how speed limits are signed internationally.
Exact factor: 1 mph = 1.609344 km/h exactly, following from the exact statute mile.

How to Convert Mile/Hour to Kilometer/Hour

To convert from Mile/Hour (mph) to Kilometer/Hour (km/h), multiply the value by 1.609344.

Formula: km/h = mph × 1.609344

Reverse: mph = km/h × 0.6213711922

Step-by-Step Example

Start with your value in Mile/Hour. For example: 5 mph
Multiply by the conversion factor: 5 x 1.609344
The result is: 8.04672 km/h

About Mile/Hour

Miles per hour is the standard unit of speed in the US and UK for vehicles and weather reporting.

Common uses: speed limits (US/UK), vehicle speed, baseball.

About Kilometer/Hour

Kilometers per hour is the most widely used unit of speed for vehicles in most countries.

Common uses: speed limits, vehicle speed, weather.

Frequently Asked Questions

What is 1 Mile/Hour in Kilometer/Hour?

1 Mile/Hour equals 1.609344 Kilometer/Hour.

How many Kilometer/Hour are in 1 Mile/Hour?

There are exactly 1.609344 Kilometer/Hour in 1 Mile/Hour. This means the conversion factor from Mile/Hour to Kilometer/Hour is 1.609344.

What is the formula to convert Mile/Hour to Kilometer/Hour?

The formula to convert Mile/Hour to Kilometer/Hour is: km/h = mph × 1.609344. For example, to convert 10 Mile/Hour to Kilometer/Hour, you would multiply 10 by 1.609344.

What is a Mile/Hour?