Use this free crosswind calculator to find the crosswind and headwind components for any runway or road. Enter wind speed, wind direction, and runway heading -- the crosswind component formula does the rest, showing full step-by-step trigonometry with sine and cosine values.
Wind & Runway Details
Wind speed unit
Crosswind Component
7.5 kts
← from the left| Wind angle: 30°
13.0 kts
Headwind
30°
Wind angle
At 15 kts from 210° on runway heading 240°, the crosswind component is 7.5 kts (from the left) and the headwind component is 13.0 kts.
Getting started
How to use this crosswind calculator
1
Select speed unit
Select knots, mph, km/h, or m/s.
2
Enter wind details
Enter the wind speed and direction (FROM) from the METAR, ATIS, or weather app.
3
Enter runway heading
Enter the runway heading (multiply the runway number by 10 to convert: Runway 24 = 240°).
4
Read results
Read your crosswind and headwind components. The direction shows left or right of the centerline.
The calculation
Step-by-step crosswind calculation
1
Find the wind angle between wind direction and runway heading
Wind Angle = |Wind Direction - Runway Heading|
= |210° - 240°| = 30°
30° is within 0-180°, use as-is.
Wind angle = 30.0°
2
Calculate the crosswind component (perpendicular to runway)
Crosswind = Wind Speed x sin(Wind Angle)
= 15 kts x sin(30.0°)
= 15 x 0.5000
= 7.5 kts (from left)
3
Calculate the headwind component (parallel to runway)
Headwind = Wind Speed x cos(Wind Angle)
= 15 kts x cos(30.0°)
= 15 x 0.8660
= 13.0 kts headwind
4
Determine the side the crosswind is from
Offset = (Wind Direction - Runway Heading + 360°) mod 360°
= (210° - 240° + 360°) mod 360° = 330°
Offset is greater than 180° -> wind from the LEFT.
Crosswind is from the LEFT
Formula
Crosswind component formula
Wind Angle = |Wind Direction - Runway Heading| (if > 180°, use 360° - result) Crosswind = Wind Speed × sin(Wind Angle) Headwind = Wind Speed × cos(Wind Angle) Side: Offset = (Wind Dir - Runway Hdg + 360°) mod 360°; if > 180° → LEFT
The sine of the wind angle tells you what fraction of the total wind strength acts perpendicular to the runway. At exactly 90°, sin(90°) = 1, so the entire wind is crosswind and headwind is zero. At 0° (wind straight down the runway), sin(0°) = 0, so crosswind is zero and all wind is headwind.
Reference Table
Quick reference -- sine and cosine values
Wind angle
sin(angle) - crosswind fraction
cos(angle) - headwind fraction
0°
0.000 (no crosswind)
1.000 (full headwind)
10°
0.174
0.985
20°
0.342
0.940
30°
0.500
0.866
45°
0.707
0.707
60°
0.866
0.500
70°
0.940
0.342
90°
1.000 (full crosswind)
0.000
Background Information
What is a crosswind component?
A crosswind component is the portion of the wind that blows perpendicular to the direction of travel -- whether a runway, a road, or any linear path. When wind blows at an angle to your direction of travel, it can be broken into two perpendicular vectors: one parallel to your path (the headwind or tailwind) and one at right angles to it (the crosswind). It is the crosswind that pushes you sideways and demands active correction.
For pilots, the crosswind component is critical because every aircraft has a maximum demonstrated crosswind component -- the highest crosswind tested and found controllable during its certification program. Exceeding this value means flying outside tested performance data, which is inherently unsafe.
For drivers, strong crosswinds are particularly hazardous for large-profile vehicles -- trucks, SUVs, buses, and trailers -- as the wind creates a lateral force that must be countered with steering input.
Interpreting
Interpreting your crosswind result
0-5 kts (0-6 mph) -- light crosswind
A crosswind in this range is negligible for most pilots. Student pilots can safely practice takeoffs and landings. Most aircraft can be landed with minimal active crosswind correction.
5-10 kts (6-12 mph) -- moderate crosswind
Requires intentional crosswind technique (crabbing on approach, wing-down on short final, or a combination). Private pilots and student solo pilots typically practice in this range.
10-15 kts (12-17 mph) -- strong crosswind
Demands competent crosswind technique. Most light aircraft have demonstrated crosswind limits in the 15-17 kts range. Student pilots should exercise judgment about Go/No-Go.
Over 15 kts (over 17 mph) -- demanding to extreme
At this range, many light aircraft are at or above their demonstrated crosswind limit. Only experienced pilots in appropriate aircraft should land in these conditions.
Tips & Common Mistakes
Tips for crosswind calculations
Use the gust factor for limit checks.
When planning Go/No-Go decisions, use the gust speed (G25 in a METAR like 15G25) as your input for the crosswind limit comparison -- the gusts, not the mean wind, will dictate your peak crosswind.
Remember the 1-in-60 approximation.
At small wind angles, crosswind ≈ (wind angle / 57.3) x wind speed. At 30°, crosswind ≈ 0.52 x wind speed -- close enough to the exact 0.5 for mental math.
Check both runway directions.
The opposite end of the same runway (heading + 180°) will give the same crosswind component but a tailwind instead of a headwind. Choose the direction that gives a headwind.
Common mistakes in crosswind calculations
Using the runway number instead of the runway heading
Runway 24 has a heading of 240°, not 24°. Entering 24 instead of 240 produces a completely wrong wind angle. Always multiply the runway number by 10 to get the heading.
Confusing wind direction convention
Aviation wind direction is reported as the direction FROM which the wind blows, in magnetic degrees. Non-aviation weather apps frequently show wind in the opposite "toward" convention.
Ignoring gusts in limit checks
A METAR wind of 12015G25KT means mean 15 kts, gusting to 25 kts. For a go/no-go crosswind limit check, you must compute the crosswind at 25 kts, not 15 kts.
FAQ
Frequently asked questions
Q
What is a crosswind component?
A crosswind component is the part of the wind that blows perpendicular to the runway (or road). When wind is not aligned with the runway, it can be split into two components: the headwind (along the runway) and the crosswind (across the runway). Pilots use the crosswind component to determine if conditions are within their aircraft certificate limits. The calculation uses trigonometry: crosswind = wind speed x sin(wind angle), where wind angle is the difference between wind direction and runway heading.
Q
How do I calculate the crosswind component formula?
The crosswind component formula is: Crosswind = Wind Speed x sin(Wind Angle), where Wind Angle = |Wind Direction - Runway Heading| (normalize to 0-180° if over 180°). The headwind formula is: Headwind = Wind Speed x cos(Wind Angle). For example, with 15 kts at 210° on runway 24 (heading 240°): Wind Angle = |210 - 240| = 30°. Crosswind = 15 x sin(30°) = 15 x 0.5 = 7.5 kts. Headwind = 15 x cos(30°) = 15 x 0.866 = 13 kts.
Q
What is the difference between headwind and tailwind?
A headwind blows toward the nose of the aircraft (or front of a vehicle) and increases the relative wind speed, which is beneficial for aircraft -- it shortens takeoff run and reduces landing speed. A tailwind blows from behind, reducing the effective wind speed and typically requiring a longer runway. A tailwind means the headwind component is negative. Pilots generally prefer a headwind for landing and avoid tailwinds beyond about 10 kts.
Q
How do I read runway headings for this calculator?
Runway numbers are the first two digits of the magnetic heading divided by 10. Runway 24 has a heading of 240°. Runway 06 has a heading of 060°. Parallel runways use L (left), C (center), and R (right) suffixes. Enter the heading -- not the number -- in the Runway Heading field. If you know only the runway number, multiply it by 10 to get the heading: Runway 18 = 180° heading, Runway 09 = 090° heading.
Q
What crosswind speed is considered dangerously high?
Most light training aircraft (e.g., Cessna 172) have a demonstrated crosswind component of 15 kts. High-performance light aircraft are typically rated to 17-20 kts. Commercial airliners can handle 30+ kts with proper technique. However, the published demonstrated limit is not a hard maximum -- it is the highest crosswind tested during certification. Many instructors recommend that student pilots treat 10 kts as their personal limit until they have more crosswind landing experience.
Q
Does wind direction mean the direction wind is coming from?
Yes -- in aviation and meteorology, wind direction is reported as the direction the wind is coming FROM. A 270° wind blows from due west toward the east. This matches the convention used in METARs, TAFs, and ATC wind reports. Enter the FROM direction in this calculator. Note: some non-aviation apps (like weather maps showing wind barbs) show the direction wind is blowing TOWARD -- if using those sources, add 180° to convert to the FROM convention.
