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Sail-to-Displacement Ratio Calculator

Calculate and understand the key performance indicator of your sailboat

Quick Samples
Try these common configurations to get started

Lightweight Racer (25ft)

Coastal Cruiser (32ft)

Heavy Offshore Cruiser (40ft)

Hull Dimensions
Enter your boat's principal dimensions
About This Tool
The Sail-to-Displacement (SA/D) Ratio is a key performance indicator for a sailboat. It compares the sail's power (sail area) to the boat's weight (displacement), providing a quick way to gauge a boat's potential speed and handling characteristics. A higher number generally indicates a more performance-oriented boat, while a lower number suggests a more docile, heavy-weather-oriented vessel.

Key Concepts:

Sail Area (SA): The engine of the boat, measured in square feet.
Displacement (D): The weight of the boat, measured in pounds.
< 14: Heavy offshore cruisers, very stable.
14-20: Typical range for coastal cruisers, a good balance.
> 20: Performance cruisers and racing boats, fast but demanding.
Frequently Asked Questions

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