True Wind Calculator

True wind

Direction —°T

Speed —kn

Beaufort —

—

Observations

Ship's course °T

Ship's speed kn

As logged — speed over ground or through the water.

Relative wind direction

Bearing from the bow °

000 ahead · 090 starboard beam · 180 astern · 270 port beam.

Relative wind speed kn

Wind diagram

Apparent wind (observed)—
Ship's motion—
True wind (result)—

Wind arrows point the way the air travels; labels give the direction the wind blows from, as recorded in the log. The true wind is the diagonal of the parallelogram formed by the apparent wind and the ship's motion.