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Convert Speed

Here you can convert units like kilometer per second, meter per second, kilometer per hour, mile per second, etc. within the speed category.

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Unit Value Actions
kilometer per second km/s
meter per second m/s SI derived unit of speed. Read more
kilometer per hour km/h Standard unit for speed limits worldwide. Read more
Unit Value Actions
mile per second mi/s
mile per hour mph Standard speed unit in US/UK. Read more
foot per second ft/s
Unit Value Actions
knot kn One nautical mile per hour. Used in aviation/marine. Read more
nautical mile per hour nmi/h

Common mistakes in speed conversion

  • A knot is one nautical mile per hour, exactly 1.852 km/h, not 1 km/h. A boat doing 20 knots travels at about 37 km/h. Multiply knots by 1.852 to get km/h.
  • Between m/s and km/h the factor is 3.6, an hour has 3,600 seconds and a kilometer 1,000 meters. Multiply m/s by 3.6 to get km/h (10 m/s = 36 km/h) and divide going the other way. Flipping the factor produces a thirteen-fold error.
  • UK and US road signs show miles per hour, not km/h. 1 mph is about 1.609 km/h, so a '70' limit means about 113 km/h. Multiply mph by 1.6 to think in km/h.

Quick conversion quiz

Score: 0

179 knot equals 206 mile per hour.

Correct answer: 179 knot = 206 mile per hour.

18 kilometer per hour equals 11.2 knot.

Correct answer: 18 kilometer per hour = 9.72 knot.

211 knot equals 243 mile per hour.

Correct answer: 211 knot = 243 mile per hour.

8.8 meter per second equals 18.8 knot.

Correct answer: 8.8 meter per second = 17.1 knot.

Definitions

meter per second (m/s)

SI derived unit of speed.

The meter per second (m/s) is the SI derived unit of speed and velocity. It is defined by the distance in meters divided by the time in seconds.

kilometer per hour (km/h)

Standard unit for speed limits worldwide.

The kilometer per hour (km/h) is a unit of speed, expressing the number of kilometers travelled in one hour. It is the most common unit for speed limits on road signs worldwide.

mile per hour (mph)

Standard speed unit in US/UK.

The mile per hour (mph) is a unit of speed expressing the number of statute miles covered in one hour. It is the standard unit for speed limits in the United States and the United Kingdom.

knot (kn)

One nautical mile per hour. Used in aviation/marine.

The knot (kn) is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h. It is used in meteorology, and in maritime and air navigation.

Frequently asked questions

How do I convert km/h to mph?

Multiply km/h by 0.621371. Example: 100 km/h ≈ 62.1 mph.

How do I convert mph to km/h?

Multiply mph by 1.609344. Example: 60 mph ≈ 96.6 km/h.

How do I convert m/s to km/h?

Multiply by 3.6. Example: 10 m/s = 36 km/h.

How do I convert km/h to m/s?

Divide by 3.6. Example: 72 km/h = 20 m/s.

What is a knot and how fast is it?

A knot is one nautical mile per hour. 1 knot equals 1.852 km/h.

Why does my quick mental math conversion not match exactly?

Rules of thumb like “divide by 1.6” are approximations. For precise results, use the exact conversion factor in the converter.

How do I use the speed converter on konvertera.nu?

Enter your speed, choose the current unit (like km/h), select the target unit (like mph), and the converter shows the result.

Popular conversions in speed