What is metre per second?

Metre per second is the SI unit of speed. It is used in physics, engineering, and scientific contexts to express velocity, and serves as the reference unit for all speed calculations in this converter.

Real-world uses

Metres per second is the SI unit of speed used in physics, engineering, and scientific research. Wind speed in meteorological data, projectile velocities, and fluid flow rates are expressed in m/s. The speed of sound at sea level is approximately 343 m/s.

History

As an SI derived unit, metres per second became the standard scientific speed unit with the adoption of the SI system in 1960. It naturally combines the base units of length (metre) and time (second).

Common mistakes

Forgetting to convert from km/h—divide by 3.6, not by 3.0 or 60. Also, confusing velocity (vector with direction) with speed (scalar magnitude), both expressed in m/s but with different physical meanings.

What is mile per hour?

Mile per hour is a unit of speed equal to one mile travelled in one hour. It is the standard unit for road speeds, vehicle performance ratings, and weather reports in the United States and United Kingdom.

Real-world uses

Miles per hour is the standard speed unit for road traffic in the United States, the United Kingdom, and a few other countries. Baseball pitching speed, hurricane wind categories (Saffir-Simpson scale), and NASCAR race speeds are quoted in mph.

History

Miles per hour became the standard speed expression in English-speaking countries with the advent of railways and later automobiles. The first US speed limit (8 mph in New York City, 1901) and British speed cameras use mph as the legal standard.

Common mistakes

Assuming mph-to-km/h conversion is a simple ×1.5—the actual factor is 1.609. Also, forgetting that UK and US speed limits both use mph, which can mislead visitors from metric countries into driving too fast or too slow.

When is this conversion used?

Converting between metre per second and mile per hour is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region. Speed limits, vehicle speedometers, and weather reports for wind speeds use different units depending on the country, making km/h to mph conversion one of the most practical speed conversions.

Worked examples

1 metre per second = 2.23693629 mile per hour

1 mile per hour = 0.44704 metre per second

How to convert metre per second to mile per hour

To convert metre per second to mile per hour, multiply the value by 2.23693629.

To convert mile per hour back to metre per second, multiply by 0.44704.

Measurement standards

The SI unit of speed is metres per second (m/s), a derived unit requiring no independent definition. The knot is defined as exactly one nautical mile (1,852 metres) per hour and is sanctioned for maritime and aeronautical navigation by the International Civil Aviation Organization.

Did you know?

The fastest human-made object is the Parker Solar Probe, which reached 635,266 km/h (about 176 km/s) in 2024 during a close pass of the Sun — fast enough to travel from New York to Tokyo in under a minute.

Quick reference: metre per second to mile per hour

metre per second	mile per hour
0.1	0.22369363
0.5	1.11846815
1	2.23693629
2	4.47387258
5	11.18468146
10	22.36936292
25	55.9234073
50	111.8468146
100	223.69362921
250	559.23407301
500	1,118.46814603
1,000	2,236.93629205

Common values

	metre per second	mile per hour
Walking speed	1.4 metre per second	3.13171081 mile per hour
City speed limit	13.9 metre per second	31.09341446 mile per hour
Highway driving	31.3 metre per second	70.01610594 mile per hour
Commercial aircraft	250 metre per second	559.23407301 mile per hour
Speed of sound (sea level)	340.29 metre per second	761.20705082 mile per hour

Available Speed units

More metre per second conversions

Assumption: Mach uses an approximate sea-level reference (about 340.29 m/s).