True Wind Speed & Direction Calculator
💨 True Wind Speed & Direction Calculator
Convert apparent wind readings to true wind for accurate sail trim and navigation decisions.
Understanding True vs Apparent Wind
The Difference Between True and Apparent Wind
True Wind: The actual wind speed and direction relative to the Earth's surface. This is what a stationary observer would feel.
Apparent Wind: The wind you feel on a moving boat, which is the vector sum of true wind and the wind created by boat movement.
Why True Wind Matters
- Sail selection based on actual conditions
- Weather pattern analysis
- Tactical racing decisions
- Anchoring and docking planning
- Accurate weather routing
Points of Sail Explained
- Close Hauled (0-45°): Sailing as close to the wind as possible
- Close Reach (45-75°): Fast and comfortable sailing angle
- Beam Reach (75-105°): Wind perpendicular to boat, often fastest point
- Broad Reach (105-135°): Wind from behind the beam
- Running (135-180°): Wind from directly behind
Frequently Asked Questions
When should I use true wind vs apparent wind?
Use apparent wind for sail trim and immediate boat handling - your sails respond to apparent wind. Use true wind for strategic decisions like sail selection, weather routing, and understanding weather patterns. Racing sailors use both: apparent for trim, true for tactics.
Why does apparent wind increase when sailing upwind?
When sailing upwind, your boat's forward motion adds to the true wind speed. If true wind is 10 knots and you're sailing at 6 knots toward it, the apparent wind will be approximately 15-16 knots. This is why boats can sail faster than the true wind speed when close hauled or reaching.