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Speed-Power Calculator

Estimate the engine power required for your boat's target speed

Quick Samples
Try these common configurations to get started

30ft Displacement Cruiser

Typical cruising sailboat or trawler

25ft Planing Sportboat

Lightweight, high-speed boat

40ft Semi-Displacement

Balances speed and efficiency

Hull Dimensions
Enter your boat's principal dimensions
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About This Tool
This calculator estimates the horsepower required to drive a boat at a certain speed. It uses different naval architecture formulas for displacement, semi-displacement, and planing hulls to provide a reliable estimate.

Key Concepts:

Hull Speed: The theoretical maximum speed of a displacement hull.
Planing: When a hull rises up and skims across the water at high speed.
Resistance: The forces (friction, wave-making) that the engine must overcome.
Power Curve: The non-linear relationship between speed and power.
Frequently Asked Questions

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