Sail Area to Displacement Ratio Calculator
Calculate and analyze your boat's sail area to displacement ratio for performance assessment.
ft²
kg
Understanding SA/D Ratio
- <16: Heavy cruising boats
- 16-18: Moderate cruising boats
- 18-20: Performance cruisers
- >20: Racing and high-performance boats
Note: Higher ratios indicate better light wind performance but may require more frequent reefing in stronger winds.
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See what's insideFrequently Asked Questions
What is a good SA/D ratio?
SA/D ratios typically range from 10-15 for cruising boats, 15-20 for cruiser-racers, and 20-30+ for racing boats. Higher ratios mean more sail power relative to weight.
How is SA/D ratio calculated?
SA/D = Sail Area (sq ft) / (Displacement in lbs / 64)^(2/3). In metric: SA/D = SA (sq m) / (Displacement in kg / 1025)^(2/3) × 3.28².