How to Calculate Buoyancy Calculator

What is Buoyancy Calculator?

Buoyancy is the upward force a fluid exerts on a submerged or floating object, equal to the weight of fluid displaced (Archimedes' Principle). An object floats when buoyant force equals or exceeds its weight; it sinks when weight exceeds buoyant force.

Formula

Buoyant force Fb = ρ_fluid × g × V_displaced

Fb: ρ_fluid × g × V_displaced — ρ_fluid × g × V_displaced

Step-by-Step Guide

1Buoyant force Fb = ρ_fluid × g × V_displaced
2ρ_fluid = fluid density (water = 1,000 kg/m³)
3g = gravitational acceleration (9.81 m/s²)
4V_displaced = volume of fluid displaced (= object volume if fully submerged)
5Object floats if object density < fluid density

Worked Examples

Input

0.1m³ wooden block in water

Result

Fb = 1000 × 9.81 × 0.1 = 981 N

If block weighs less than 981N, it floats

Input

Steel ball (density 7,800 kg/m³) in water

Result

Sinks — 7,800 > 1,000 (water density)

Steel is 7.8× denser than water

Frequently Asked Questions

What is Buoyancy?

Buoyancy is the upward force a fluid exerts on a submerged or floating object, equal to the weight of fluid displaced (Archimedes\. Use this calculator for accurate, instant results.

How accurate is the Buoyancy calculator?

The calculator uses the standard published formula for buoyancy. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Buoyancy calculator use?

This calculator works with kilograms, inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Buoyancy calculator use?

The core formula is: Buoyant force Fb = ρ_fluid × g × V_displaced. Each step in the calculation is shown so you can verify the result manually.