Crosswind Calculator
Enter the runway and the wind to see the crosswind and headwind or tailwind, including gusts and the other end of the runway.
Number such as 27 or 09L, or an exact heading such as 273.
Where the wind blows from.
How your wind is split up
Crosswind = wind × sin(angle). Headwind = wind × cos(angle).
- 1
Runway heading
Runway 27: 27 × 10
= 270° - 2
Angle off the runway
300° vs 270°
= 30° from the right - 3
Crosswind part
20 × sin 30°
= 20 × 0.50
= 10 kt - 4
Headwind part
20 × cos 30°
= 20 × 0.87
= 17 kt headwind
Read more: the formula, the clock rule and true vs magnetic
The wind is split into two parts: one along the runway (headwind or tailwind) and one across it (crosswind). Both depend on the angle between the wind direction and the runway heading.
crosswind = wind speed × sin(angle)
headwind = wind speed × cos(angle)
If the headwind comes out negative, it is a tailwind.
Worked example
Runway 27 has a heading of 270°. With wind from 300° at 20 kt, the angle is 30°. The crosswind is 20 × sin 30° = 10 kt from the right. The headwind is 20 × cos 30° = 17 kt.
Quick mental rule
Pilots often estimate crosswind with the "clock" method: each 15° of angle is a quarter of the hour.
| Angle off the runway | Crosswind is about | Exact |
|---|---|---|
| 15° | ¼ of the wind | 26% |
| 30° | ½ of the wind | 50% |
| 45° | ¾ of the wind | 71% |
| 60° or more | All of the wind | 87–100% |
True or magnetic?
Runway numbers are magnetic. Winds in a METAR or TAF are given in degrees true, while ATIS and tower winds are magnetic. Where magnetic variation is large, correct a METAR wind before using it here.
For planning and education. Always use your aircraft's approved limits and the latest reported wind for operational decisions.