Crosswind Calculator
Enter the wind direction, wind speed, and runway number (or a custom heading) to instantly resolve the wind into its crosswind and headwind/tailwind components. The crosswind limit gauge shows at a glance whether the wind is within the typical general-aviation limit. Switch speed units between knots, mph, km/h, and m/s.
What is a crosswind component?
Wind rarely blows perfectly aligned with a runway. The crosswind component is the portion of the wind that blows perpendicular to the runway centreline - the part that tries to push the aircraft sideways. The headwind/tailwind component is the portion blowing along the runway axis. Pilots must resolve the total wind into these two components because aircraft performance charts and crosswind limits are always given in component form, not as a raw wind-angle value. A 20-knot wind at 45 degrees off the runway heading produces about 14 knots of crosswind and 14 knots of headwind - not 20 knots of either.
How to use this calculator
Enter the wind direction (the direction the wind is blowing FROM, in degrees), the wind speed in your preferred units, and either the runway number (01-36) or a custom runway heading. The calculator immediately shows the crosswind component, the headwind or tailwind component, and which side the wind is coming from. Enter your aircraft's demonstrated or certificated crosswind limit to see a gauge of how much of the limit you are using. You can also enter a gust speed to check the worst-case crosswind at peak gusts. The chart below shows how crosswind and headwind components vary across all possible wind angles for your current wind speed, which is useful for quickly seeing at what angle the limit is crossed.
The crosswind formula explained
The calculation uses vector decomposition. First, the angle difference between wind direction and runway heading is computed and normalised to a range of -180 to +180 degrees (negative for left-of-centreline wind, positive for right). Then the crosswind component equals the wind speed multiplied by the sine of that angle, and the headwind component equals the wind speed multiplied by the cosine. The sign of the headwind tells you whether it is a headwind (positive cosine, wind from in front) or a tailwind (negative cosine, wind from behind). A direct headwind produces zero crosswind and maximum headwind. A 90-degree crosswind produces maximum crosswind and zero headwind or tailwind.
Reading runway numbers and wind direction
Runway numbers range from 01 to 36 and represent the magnetic heading of the runway divided by 10, rounded to the nearest ten degrees. Runway 27 points toward 270 degrees (west), runway 09 toward 090 degrees (east), and so on. Wind direction in aviation ATIS and METAR reports is always given as the direction the wind is blowing FROM, in degrees magnetic (e.g. "Wind 270 at 15" means the wind blows from the west at 15 knots). Both the wind direction and the runway heading must be in the same reference system - magnetic for standard operations - for the calculation to be valid.
Crosswind limits and go/no-go decisions
Every certified aircraft has a demonstrated crosswind value published in its Pilot Operating Handbook or Airplane Flight Manual. This is not always a hard limit - it is the maximum crosswind at which the aircraft was successfully demonstrated during flight testing, and it may not represent the absolute aerodynamic limit. Operators and training organisations often set lower in-house limits for student pilots or line operations. When the crosswind component approaches the limit, technique becomes critical: the crab method maintains wings-level tracking on approach and is transitioned to a sideslip (wing-low) just before touchdown, putting the upwind main gear down first. For tailwinds, even small components increase ground roll significantly and must be checked against the performance tables.
Typical crosswind limits by aircraft category
| Aircraft type | Typical crosswind limit | Notes |
|---|---|---|
| Ultralight / microlight | 8-10 kt | Often placarded lower than certificated |
| Cessna 172 (Skyhawk) | 15 kt | FAA demonstrated value |
| Piper PA-28 (Cherokee) | 17 kt | FAA demonstrated value |
| Beechcraft Bonanza | 17 kt | FAA demonstrated value |
| Cirrus SR22 | 21 kt | FAA demonstrated value |
| Boeing 737 | 35-38 kt | Varies by series and surface condition |
| Airbus A320 | 38 kt | Dry runway; lower for contaminated |
| Military trainer (T-6 Texan II) | 23 kt | USAF/USN operating limit |
These are representative demonstrated crosswind values. Always consult your specific aircraft Pilot Operating Handbook (POH) or Airplane Flight Manual (AFM) for the certificated limit.
Frequently asked questions
What is the crosswind formula?
The crosswind component equals wind speed multiplied by the sine of the angle between the wind direction and the runway heading. In symbols: Crosswind = V x |sin(alpha)|, where alpha is the normalised angle difference. The headwind or tailwind component equals V x cos(alpha). Both components together reconstruct the full wind vector.
How do I convert a METAR wind to crosswind?
Take the wind direction and speed from the METAR (e.g. "27015G22KT" means from 270 degrees at 15 knots gusting 22 knots). Enter 270 as wind direction, 15 as wind speed, and 22 as gust speed in this calculator, then select the runway you are using. The calculator gives the crosswind and headwind at both steady and gust values.
What is a safe crosswind component for student pilots?
Most flight training organisations set an in-house limit of around 8-10 knots for student solo crosswind operations, even if the aircraft is certificated for more. The aircraft capability and the pilot skill level are both factors. Always follow your school's specific limits and your instructor's guidance.
Does a headwind improve or hurt performance?
A headwind reduces ground speed for a given airspeed, which shortens takeoff and landing rolls and improves climb gradient. A tailwind has the opposite effect: it increases ground roll, extends the stopping distance on landing, and reduces the climb gradient. Even a small tailwind component can add significantly to runway length required, so it should always be checked against performance data.
What does wind from the left or right mean for technique?
Wind from the left means the aircraft will be pushed toward the right side of the runway if uncorrected. On approach, apply left aileron (upwind wing down) to hold the centreline in a sideslip, or crab into the wind. On touchdown, the upwind (left) main gear contacts first, followed by the downwind main gear, then the nose gear. Wind from the right reverses all of these corrections.