Km/h to m/s Converter

How many meters per second are in one km/h?

One kilometer per hour is 0.277778 meters per second, which is exactly 1/3.6 m/s. The number 3.6 appears because an hour holds 3,600 seconds while a kilometer holds 1,000 meters, and 3,600 ÷ 1,000 = 3.6.

m/s = km/h × 1,000 ÷ 3,600 = km/h ÷ 3.6To go back, multiply meters per second by 3.6.

Why you need both

Kilometers per hour is the unit for roads, railways and weather reports: it keeps vehicle speeds in a familiar range of tens and hundreds. Meters per second is the coherent SI unit of speed, so it is the one physics formulas expect. Kinetic energy, momentum, acceleration and projectile calculations only come out in joules, newton-seconds or m/s² when the speed is in m/s.

Converting is therefore a routine first step: read the speed off a speedometer in km/h, turn it into m/s, then substitute it into the formula.

How to convert km/h to m/s

1. Type the speed in km/h into the first box.
2. Read the speed in m/s from the second box as it updates.
3. Check by hand by dividing the km/h figure by 3.6.

Example 1. A cyclist rides at 27 km/h. 27 ÷ 3.6 = 7.5 m/s.

Example 2. A person walks at a steady 5 km/h. 5 ÷ 3.6 ≈ 1.3889 m/s, so a walker covers about 1.4 meters every second.

Example 3. A motorway speed of 130 km/h. 130 ÷ 3.6 ≈ 36.11 m/s, which means the vehicle covers more than 36 meters every second.

km/h to m/s conversion table

Handy anchors and next steps

Remember that 36 km/h is 10 m/s. Any speed can then be scaled from that anchor: 72 km/h is 20 m/s, and 90 km/h is 25 m/s. Going the other direction, 1 m/s is 3.6 km/h, so a speed of sound near 343 m/s is about 1,235 km/h.

The reverse conversion has its own page, the m/s to km/h converter. If you need miles per hour as well, use the km/h to mph converter. To go from distance and time to a speed in the first place, try the speed calculator, and for the energy of a moving object see the kinetic energy calculator.