Speed Converter

Type a number into any of the four fields — Kilometers / hour, Miles / hour, Meters / second, or Knots — and the other three recalculate immediately using meters per second as the common reference. There’s no separate convert button; every keystroke updates the whole set live. This is handy for comparing a car’s speedometer reading in km/h against a US speed limit in mph, checking wind speed reported in m/s against a knots-based marine or aviation forecast, or converting a runner’s race pace between units.