I'm solving a physics kinematics problem that says a car is traveling at 100 km/h, but my equation needs the speed in m/s — what number do I use?

100 km/h = 27.78 m/s. That's highway speed; the car travels about 27.78 meters every second.

My lab partner recorded a speed in km/h but I need m/s for my SI-unit equation — what's the quickest way to convert it?

Divide by 3.6. Example: 36 km/h ÷ 3.6 = 10 m/s. This conversion is mathematically exact (3.6 = 3600 seconds / 1000 meters).

Why do all my chemistry textbooks use m/s in equations and examples, but real-world speeds are usually described in km/h?

Meters per second is the SI (International System) base unit for speed. Physics equations assume SI units. Using m/s ensures formulas for kinematics, momentum, and energy work correctly.

My cycling app shows my average speed as 28 km/h — how far do I travel each second?

28 km/h = 7.78 m/s. So yes, you're covering nearly 8 meters every second. That's useful to know when estimating stopping distance or timing traffic light gaps during a fast ride. For the reverse conversion, see [m/s to km/h](/speed/ms-to-kmh/).

Kilometers per Hour (km/h) to Meters per Second (m/s) Converter

Enter a value to instantly convert between speed units.

From

Precision4 dp

1 Kilometer per Hour = 0.2778 Meter per Second

Key Formulas

Kilometer per Hour → Mile per Hour

mph = km/h × 0.621371

Mile per Hour → Kilometer per Hour

km/h = mph × 1.60934

Knot → Mile per Hour

mph = kn × 1.15078

Mile per Hour → Knot

kn = mph × 0.868976

Formula

m/s = km/h ÷ 3.6

To convert kilometers per hour to meters per second, divide by 3.6. This is useful for physics problems, engineering calculations, and translating real-world speeds into SI units used in science.

Source: NIST SP 811, Table B.8

Frequently Asked Questions

Real-World Examples

Slow walking pace. About 2.2 mph; realistic human walking speed.

3.6 km/h = 1 m/s

Fast cycling or skateboarding speed. Athletic pace during casual activity.

36 km/h = 10 m/s

Fast car speed on a city street. Reasonable driving in traffic.

72 km/h = 20 m/s

Typical jet aircraft cruising speed. Commercial aircraft cruise around 900 km/h (Mach 0.85 at altitude).

900 km/h = 250 m/s

kmh to mph mph to kmh knots to mph mph to knots ms to kmh

Kilometers per Hour (km/h) to Meters per Second (m/s) Converter

Key Formulas

Formula

Frequently Asked Questions

Real-World Examples

Related Converters