Kayak Wind Resistance Calculator
Calculate wind resistance and speed penalty on a kayak from wind speed and paddle heading.
Returns drag, headwind, and watts to maintain target pace.
Wind exerts a drag force on your kayak and body above the waterline. The drag force increases with the square of the apparent wind speed — doubling wind speed quadruples the drag.
Drag force formula: F = 0.5 × rho × Cd × A × v²
Where:
- rho = air density (~1.225 kg/m³ at sea level)
- Cd = drag coefficient (~1.0 for a seated paddler broadside)
- A = frontal area (approx. 0.5 m² for paddler + kayak bow)
- v = apparent wind speed (m/s)
Effect on paddling speed: Each 1 N of drag requires approximately 0.3 W of extra power at typical kayak speeds. At 4 knots, a 20 N headwind drag reduces effective speed by roughly 0.5–1 knot.
Practical wind thresholds for sea kayaking:
- Force 1–2 (1–11 km/h): Negligible effect, ideal conditions
- Force 3 (12–19 km/h): Light headwind: slight effort increase
- Force 4 (20–28 km/h): Moderate headwind: noticeable slowdown
- Force 5 (29–38 km/h): Fresh breeze: significant effort increase, spray
- Force 6+ (39+ km/h): Strong wind: advanced paddlers only, high risk
Tailwind benefit: A following wind reduces headwater drag and can add 0.5–1.5 knots to your effective speed. Unlike a headwind, a strong tailwind can make control harder — quartering waves may require constant bracing.