Crosswind & Headwind Component Calculator

Any wind can be split into two components relative to the direction you're flying: crosswind, which pushes the aircraft sideways off the centerline, and headwind (or tailwind), which acts along the runway. Both follow from simple trigonometry on the angle between the wind direction and the runway heading: crosswind = wind speed × sin(angle), headwind = wind speed × cos(angle). A 90° crosswind puts the full wind speed sideways with zero along the runway; a direct headwind is the opposite.

The sign of each component tells you which way it acts: a positive cosine means a headwind (slows your ground speed on takeoff/landing roll), a negative one means a tailwind. Whether the crosswind pushes from the left or the right follows from which side of the runway heading the wind direction falls on.

Wind speed can be entered in knots, mph, or km/h — whichever unit your wind report uses — since the trigonometry scales linearly and the result comes out in that same unit; there's nothing to convert.