Buoyancy Experiment Calculator

Test whether an object floats or sinks and calculate the exact buoyant force acting on it, based on Archimedes’ principle — great for classroom buoyancy experiments.

Fluid

Object Volume (Submerged)

cm³

Object Mass

What This Calculator Does

This calculator applies Archimedes’ principle to find the buoyant force on an object submerged in a fluid, and compares it to the object’s weight to predict whether it floats or sinks — useful for classroom or home buoyancy experiments.

The Formula

Archimedes’ principle states that the buoyant force equals the weight of fluid displaced: F_b = ρ_fluid · g · V_displaced, where ρ_fluid is the fluid’s density, g is gravitational acceleration (9.81 m/s²), and V is the submerged volume. If this buoyant force is greater than or equal to the object’s weight, the object floats; if it’s less, the object sinks.

Note: This is an idealized calculation for general educational purposes. It assumes the entered volume is fully submerged and ignores factors like surface tension, fluid viscosity, and irregular object shapes that can affect real experimental results.

Last reviewed August 2026