Average Velocity Calculator
Compute average velocity v = Δs/Δt from distance and time, in km/h or m/s.
v = — m/s = — km/h
Average speed: v = Δs/Δt
Average speed is the total distance traveled divided by the total time: v = Δs/Δt. The SI unit is m/s, but km/h is more common for everyday travel (divide km/h by 3.6 to get m/s). A crucial point: average speed is not the average of the speeds. Classic example: you drive 60 km at 60 km/h (1 hour) and return at 30 km/h (2 hours). Total: 120 km in 3 h, so v_avg = 40 km/h — not 45. Because more time is spent at the slower speed, it dominates the average. Average speed also differs from instantaneous speed (the value a derivative or speedometer gives at one moment).
Applications
Personal running/cycling pace, flight planning (groundspeed vs airspeed, since wind shifts the result), boating (speed over water vs over ground), road-trip ETA, race analysis. Scalar vs vector matters: running 100 m out and 100 m back in 1 min gives a scalar average speed of 12 km/h but a vector average velocity of 0 — you ended where you started.
FAQ
Why isn't average speed the average of two speeds? Because each speed segment may take a different amount of time. The slower leg takes longer and therefore weighs more in the average.
How do I convert km/h to m/s? Divide by 3.6. Example: 108 km/h ÷ 3.6 = 30 m/s.
Speed or velocity? Speed is a scalar (magnitude only). Velocity is a vector (magnitude + direction). On a round trip, the average velocity can be zero while the average speed is not.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.