Crosswind Calculator
A crosswind calculator breaks total wind into two components: the crosswind (perpendicular to your heading) and the headwind or tailwind (parallel). If the wind is 270° at 15 knots and your runway is 240°, the crosswind is about 7.5 knots from the right and the headwind is about 13 knots. Pilots, cyclists, and sailors all use these components for planning.
The wind component formulas are based on simple trigonometry:
- Crosswind = Wind Speed * sin(angle)
- Headwind = Wind Speed * cos(angle)
Where the angle is the difference between the wind direction and your heading. A positive headwind value means wind is opposing your motion (good for takeoff/landing performance). A negative value means you have a tailwind.
**Quick Mental Math for Pilots:** - **30° off the nose:** Crosswind = 1/2 of wind speed - **45° off the nose:** Crosswind = 3/4 of wind speed - **60° off the nose:** Crosswind = nearly full wind speed - **90° (direct crosswind):** Crosswind = full wind speed **Aircraft Crosswind Limits (examples):** - **Cessna 172:** 15 knots demonstrated crosswind - **Boeing 737:** 33 knots maximum crosswind - **Airbus A320:** 38 knots maximum crosswindFor cycling, a 15 mph crosswind at 90° to your direction of travel pushes you sideways with the full 15 mph. This can be dangerous for lightweight riders on open roads or bridges. A 45° quartering headwind at 20 mph delivers about 15 mph crosswind and 14 mph headwind.