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Stability Calculator

Analyze key boat stability metrics like GM, Roll Period, and Comfort Ratio.

Quick Samples
Try these common configurations to get started

30ft Cruising Sailboat

A well-balanced coastal cruiser.

25ft Racing Yacht

A stiff, performance-oriented boat.

45ft Offshore Cruiser

A heavy, comfortable bluewater boat.

Hull Dimensions
Enter your boat's principal dimensions
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About This Tool
This calculator provides a high-level analysis of a boat's stability. By providing key metrics like Metacentric Height (GM) and beam, it estimates important characteristics like the boat's roll period and comfort ratio. This tool is intended for educational purposes and for comparing different designs, not as a substitute for a full analysis by a naval architect.

Key Concepts:

Metacentric Height (GM): The primary measure of initial stability. Higher is stiffer.
Ballast Ratio: The percentage of total weight that is ballast. A key driver of stability.
Roll Period: The time it takes for a boat to complete one roll cycle. Longer is usually more comfortable.
Comfort Ratio: A formula to estimate a boat's seakindliness. Higher values suggest more comfort in waves.
Frequently Asked Questions

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