Mile/Hour to Kilometer/Second Converter

Speed Converter

18 units available

Decimals:

From

To

0.000447

1 mph = 0.000447 km/s

Formula:

km/s = mph × 0.00044704

With your value: 1 mph = 0.00044704 km/s

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/Second conversions

2 mph to km/s 3 mph to km/s 4 mph to km/s 5 mph to km/s 6 mph to km/s 7 mph to km/s 8 mph to km/s

Mile/Hour to Kilometer/Second Conversion Table

Mile/Hour (mph)	Kilometer/Second (km/s)
0.5	0.000224
1	0.000447
2	0.000894
5	0.002235
10	0.00447
15	0.006706
20	0.008941
25	0.011176
50	0.022352
100	0.044704
250	0.11176
500	0.22352
1000	0.44704

Kilometer/Second to Mile/Hour Conversion Table

Kilometer/Second (km/s)	Mile/Hour (mph)
0.5	1,118.468146
1	2,236.936292
2	4,473.872584
5	11,184.68146
10	22,369.362921
15	33,554.044381
20	44,738.725841
25	55,923.407301
50	111,846.814603
100	223,693.629205
250	559,234.073014
500	1,118,468.146027
1000	2,236,936.292054

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/Second (km/s)

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

How to Convert Mile/Hour to Kilometer/Second

To convert from Mile/Hour (mph) to Kilometer/Second (km/s), multiply the value by 0.00044704.

Formula: km/s = mph × 0.00044704

Reverse: mph = km/s × 2,236.9362920544

Step-by-Step Example

Start with your value in Mile/Hour. For example: 5 mph
Multiply by the conversion factor: 5 x 0.00044704
The result is: 0.002235 km/s

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/Second

The kilometer/second (km/s) is a unit of speed and velocity. One kilometer/second equals 1000 metre per seconds. UnitConvertLab converts it against every other speed unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.

Common uses: speed calculations, engineering and science, education.

Frequently Asked Questions

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

There are exactly 0.00044704 Kilometer/Second in 1 Mile/Hour. This means the conversion factor from Mile/Hour to Kilometer/Second is 0.00044704.

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

The formula to convert Mile/Hour to Kilometer/Second is: km/s = mph × 0.00044704. For example, to convert 10 Mile/Hour to Kilometer/Second, you would multiply 10 by 0.00044704.

What is a Mile/Hour?