Fluid Mechanics
Buoyancy Calculator
Calculate buoyant force using Archimedes' principle: F_b = ρVg. Determines whether an object floats or sinks and shows how deep it sits in the fluid.
F_b = ρ_fluid × V_submerged × g
Select fluid, object and volume to calculate.
Archimedes' Principle
Archimedes' principle states that the buoyant force on a submerged object equals the weight of fluid it displaces: F_b = ρVg. An object floats when its average density is less than the fluid density — regardless of its total mass or volume. This is why steel ships float: their hollow interior gives them an average density less than water.