Conversions

mph, km/h, m/s: A Quick Speed Conversion Guide

Morecalcs Team 2026-08-07· 4 min

Instant mental conversions for road, track, and physics.

The three factors

1 mph = 1.609 km/h
1 km/h = 0.278 m/s
1 mph = 0.447 m/s

Mental math

mph → km/h: add 60%. km/h → mph: subtract 40%. Close enough for road signs.

Why runners use pace instead

Speed is distance per time. Pace is time per distance (min/km). Pace makes even splits easier to plan.

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