Crosswind Calculator
Enter a runway and the reported wind to get the crosswind component and the headwind or tailwind component, in knots, mph, or km/h. Add a gust to see the crosswind at the peak. Crosswind is wind speed times the sine of the angle between the wind and the runway, so a wind 30° off the runway puts half its speed across it.
Educational tool, not for flight planning. What it leaves out
Runway 27 points about 270° magnetic.
The direction the wind blows from.
A meaningful crosswind component. Compare it against your aircraft's published figures.
Use the same reference for the runway and the wind. Runway numbers and tower or ATIS winds are magnetic, so they compare directly. METAR and TAF winds are true: convert them with local variation first, or enter the runway's true bearing in Degrees mode. For example, 270° magnetic with 15° east variation is 285° true.
Crosswind Formula
Find the angle between the wind direction and the runway heading, then split the wind speed with sine and cosine:
Angle = Wind Direction - Runway Heading
Crosswind = Wind Speed × sin(Angle)
Headwind = Wind Speed × cos(Angle)
Worked example: runway 27 (270°) with wind from 300° at 15 kt is a 30° angle. The crosswind is 15 × sin 30° = 7.5 kt from the right, and the headwind is 15 × cos 30° = 13.0 kt.
A negative headwind is a tailwind. Wind from an angle between 0° and 180° to the right of the runway heading is a crosswind from the right; anything else is from the left.
Crosswind Rule of Thumb: the Clock Method
Treat the angle between the wind and the runway as minutes on a clock face. The share of the clock that has passed is roughly the share of the wind acting across the runway. It is close at 15° and 30° and runs high from 45° on, so larger angles err on the cautious side.
15 minutes is 1/4 of an hour. Exact share: 26%.
30 minutes is 1/2 of an hour. Exact share: 50%.
45 minutes is 3/4 of an hour. Exact share: 71%.
60 minutes is a full hour. Exact share: 87%.
Crosswind Component Chart
Crosswind component, rounded to the nearest whole unit. Find the angle between the wind and the runway on the left and the wind speed across the top. Use the unit switch above to change the column labels; the shares are the same in any unit.
| Angle | Share | 5 kt | 10 kt | 15 kt | 20 kt | 25 kt | 30 kt |
|---|---|---|---|---|---|---|---|
| 10° | 17% | 1 | 2 | 3 | 3 | 4 | 5 |
| 20° | 34% | 2 | 3 | 5 | 7 | 9 | 10 |
| 30° | 50% | 3 | 5 | 8 | 10 | 13 | 15 |
| 40° | 64% | 3 | 6 | 10 | 13 | 16 | 19 |
| 50° | 77% | 4 | 8 | 11 | 15 | 19 | 23 |
| 60° | 87% | 4 | 9 | 13 | 17 | 22 | 26 |
| 70° | 94% | 5 | 9 | 14 | 19 | 23 | 28 |
| 80° | 98% | 5 | 10 | 15 | 20 | 25 | 30 |
| 90° | 100% | 5 | 10 | 15 | 20 | 25 | 30 |
Typical Crosswind Limits
Cessna 152/172 demonstrated: 12-15 kt. Student training typically limited to 5-10 kt.
Piper PA-28, Cessna 182. Most light singles have demonstrated crosswind of 15-17 kt.
Baron, King Air. Higher wing loading and more powerful controls increase limits.
CRJ, ERJ series. Limits vary by runway condition (dry vs wet vs contaminated).
Boeing 737, Airbus A320. Dry runway limits; reduced for wet/contaminated conditions.
The figures above are rough illustrations only. Refer to your aircraft's POH/AFM for its published maximum demonstrated crosswind component, and to your operator for any stricter limit.
Not for flight planning
This tool does trigonometry on a steady wind and nothing more. The result excludes runway surface and contamination, runway length and slope, density altitude, turbulence, wind shear, control authority, and your own currency. Whether a given component is acceptable is answered by your aircraft's POH/AFM and any operator limitations, not by this page. Note also that a published maximum demonstrated crosswind component is a certification test result, not necessarily a regulatory operating limit. Get a full official briefing before any flight.
Understanding Crosswind Components
What is Crosswind?
Crosswind is the component of wind that blows perpendicular to the runway. It pushes the aircraft sideways and requires correction during takeoff and landing to maintain runway centerline.
Runway Selection
When possible, choose the runway that gives you the most headwind and least crosswind. A headwind is beneficial as it reduces ground speed and shortens takeoff/landing distance.
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Frequently Asked Questions
How do you calculate the crosswind component?
Subtract the runway heading from the wind direction to get the angle between them. Crosswind = wind speed × sin(angle), and headwind = wind speed × cos(angle). For runway 27 (270°) with wind from 300° at 15 knots, the angle is 30°, so the crosswind is 15 × 0.5 = 7.5 knots from the right and the headwind is 15 × 0.866 = about 13 knots.
What is the clock method for estimating crosswind?
Read the angle between the wind and the runway as minutes on a clock. 15° is a quarter of the hour, so about a quarter of the wind is crosswind; 30° is half; 45° is three quarters; 60° or more counts as all of it. The exact shares are 26%, 50%, 71%, and 87%, so the shortcut runs high at larger angles, which errs on the cautious side.
Should I use magnetic or true wind direction for crosswind?
Use the same reference for the runway and the wind. Runway numbers and tower or ATIS winds are magnetic, so they can be compared directly. METAR and TAF winds are reported relative to true north, so convert them with the local magnetic variation, or compare them against the runway's true bearing. Where variation is large, mixing the two can noticeably change the result.
How do gusts affect the crosswind component?
The angle stays the same, so the gust speed splits into components the same way the steady wind does. Wind from 300° at 15 knots gusting 25 on runway 27 gives 7.5 knots of crosswind steady and 12.5 knots in the gusts. Enter a gust in this calculator to see both. How to fly a gusty crosswind comes from your aircraft's POH and your training.
What is the maximum demonstrated crosswind component?
It is the strongest crosswind component flown during the aircraft's certification testing, published in the POH or AFM. For the Cessna 172 it is 15 knots. It is a tested value rather than necessarily a regulatory limit, and an operator or flight school may set a stricter limit of its own.
What is the difference between a headwind and a tailwind component?
The headwind component is the part of the wind blowing straight down the runway toward you. It lowers groundspeed and shortens takeoff and landing distances. When the wind is more than 90° off the runway heading, that component turns into a tailwind, which raises groundspeed and lengthens those distances. Many aircraft publish tailwind limits in the POH or AFM.
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