Kilometers per second to miles per hour

Type a value in kilometers per second to see it in miles per hour straight away, or type in the second box to convert back.

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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.

How to use it

  1. Type the value in the kilometers per second box.
  2. Read the result in miles per hour as you type, and pick the precision you need.
  3. Swap the direction to convert back, or copy the result.

How it is calculated

mph = km/s × 2,236.936292

Multiply the value in kilometers per second by 2,236.936292 to get miles per hour.

Example

To convert 25 km/s to miles per hour: 25 × 2,236.936292 = 55,923.4 mph.

Conversion table

Kilometers per second (km/s)Miles per hour (mph)
12,236.94
24,473.87
36,710.81
511,184.7
1022,369.4
2044,738.7
2555,923.4
50111,847
100223,694
250559,234
5001,118,470
1,0002,236,940

About the units

Kilometer per second
Covering 1000 meters in one second. It is used for satellites, rockets and astronomical objects.
Mile per hour
Covering one international mile (1609.344 m) in one hour, exactly 0.44704 m/s. It is used on roads in the United States and the United Kingdom.

Limits and caveats

  • Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
  • Both unit factors are exact by their official definitions.

Questions about this tool

How many miles per hour are in one kilometer per second?

1 km/s = 2,236.94 mph exactly.

How do I convert kilometers per second to miles per hour?

Use mph = km/s × 2,236.936292. For example, 25 km/s = 55,923.4 mph.

How many kilometers per second are in one mile per hour?

1 mph = 0.00044704 km/s.

How do I convert km/h to m/s in my head?

Divide by 3.6, because an hour is 3600 seconds and a kilometer is 1000 meters. For example 72 km/h is 20 m/s; multiply by 3.6 to go back.

Why do Mach values differ between sources?

The speed of sound depends on air temperature. We use 340.294 m/s at sea level and 15 °C; at 11 km altitude it is about 295 m/s, so Mach 1 is slower there.