Resistance
Calculators
Hydrodynamic resistance prediction and propulsion sizing tools for displacement, semi-displacement and high-speed vessels.
Insel & Molland Catamaran Calculator
Industry-standard empirical resistance prediction for displacement catamarans. Viscous, wave-making, and interference factors estimation.
Savitsky Planing Hull Calculator
Industry standard for hard-chine planing craft. Predicts trim angle, lift coefficient, wetted area, and total hydrodynamic resistance.
Holtrop & Mennen Resistance Calculator
Most widely used empirical method for displacement vessels. Covers friction, appendages, wave-making, bulb, and transom stern.
William Froude Method
Foundation of resistance decomposition into frictional and residuary drag components for general hulls.
John H. Michell Theory
Theoretical wave resistance calculations based on thin-ship theory, integrated with empirical friction coefficients.
Leo Lazauskas / Michell-based
Advanced numerical wave resistance and trim evaluation tailored for slender monohulls and catamaran designs.
Odd M. Faltinsen Methods
Semi-empirical and analytical drag prediction formulations designed for high-speed displacement and planing hulls.
D. Fung Method
Alternative catamaran resistance formulation based on regression curves from systematic experimental series.
H. Y. Kwon Method
Empirical resistance estimation formulas derived specifically from model database regressions of fishing boats.
John H. Gerr Method
Simple and fast preliminary design resistance and power sizing method for recreational small craft.
Daniel H. Harvald Method
Classic empirical approach using charts and diagrams for preliminary resistance estimates of cargo hulls.
J. Hollenbach Method
Modern regression-based resistance prediction method tailored for single-screw cargo ships and tankers.
J. Compton Method
Empirical drag estimation method suitable for preliminary hull design of small displacement craft.
A. Clement Method
Yacht-specific empirical resistance prediction model tailored for sailing hull forms.
Douglas Phillips-Birt Method
Traditional yacht design empirical approach for estimating sailing yacht drag characteristics.