Beaufort Scale Converter (Wind Force)

What this tool does

Admiral Francis Beaufort's scale began in 1805 as a description of what the wind did to a warship's sails; today it is defined by wind speed measured 10 m above the ground, in the bands published by the World Meteorological Organization. Force 6 is where small boats are usually advised to stay in harbour, force 8 is a gale and force 12 hurricane force. Forecasts give mean speeds — gusts can be half as strong again — and the speeds behind the scale's names differ slightly between national weather services.

Formula

Beaufort force from the WMO wind-speed bands (m/s, 10 m above the ground) · v ≈ 0.836 × B^(3/2) m/s

Variables

Worked example

Limitations

• The default values are typical reference figures, not measurements of your situation. Replace them with your own data whenever you have it.
• The calculation runs at full precision and only the display is rounded. If you copy an intermediate value and retype it, small differences can appear.