Average speed calculator

Calculate average speed from distance and time, in km/h and m/s.

Average speed

80 km/h

In meters per second22.22 m/s

Total time1.5 h

How the calculation works

Average speed is the distance traveled divided by total time: v = d ÷ t. To convert km/h to m/s, divide by 3.6.

Is average speed the same as instantaneous speed?

No. The average covers the whole trip; instantaneous is at a specific moment (the speedometer).

Why isn't round-trip speed the simple average?

Because you spend more time at the slower speed. For the same distance, use the harmonic mean.

How to convert to m/s?

Divide km/h by 3.6. E.g. 90 km/h = 25 m/s.

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Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources