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Estimate boat top speed using Crouch's Formula.
Calculate theoretical top speed in MPH, Knots, and KPH.
Uses industry standard formula for hull efficiency.
Presets for Runabouts, Cruisers, Hydroplanes, and more.
The Boat Speed Calculator helps boat owners and enthusiasts estimate the potential top speed of a vessel based on its weight and horsepower. It uses Crouch's Formula, a widely accepted method for predicting boat performance.
Input the total weight of the boat including engine, fuel, and gear.
Input the total shaft horsepower of the engine(s).
Choose the hull type that best matches your boat to set the efficiency constant.
See the estimated top speed in MPH, Knots, and km/h.
Include engine, fuel, passengers, and gear.
Enter weight and horsepower to see the estimated speed.
Uses the formula: Speed = C / √(Weight/HP). 'C' is a constant based on the hull type and efficiency.
Total weight significantly impacts speed. Ensure you include fuel (approx 6 lbs/gallon), gear, and passengers.
Different hulls have different 'C' constants. Racing hulls (Hydroplanes) are more efficient than heavy Cruisers.