Calculate the buoyant force (Archimedes' force) acting on an object submerged in a fluid, using the formula F_b = ρ × V × g.

Buoyant Force: 4,903.33 N (≈ 500.00 kgf)

Formula: F_b = ρ × V × g. Valid for any fluid (liquid or gas).

What is Archimedes' Principle?

Archimedes' principle states that any object, totally or partially submerged in a fluid, experiences an upward buoyant force equal to the weight of the fluid displaced by the object. This fundamental law of physics was discovered by the ancient Greek mathematician Archimedes around 250 BC.

F_b = ρ × V × g

Where:

• F_b — buoyant force (Newtons, N)
• ρ — density of the fluid (kg/m³)
• V — volume of fluid displaced (m³)
• g — gravitational acceleration (m/s²)

The buoyant force is always directed upward and is equal in magnitude to the weight of the displaced fluid. This principle explains why:

• Ships float — even heavy steel ships displace enough water to match their weight
• Submarines work — by controlling their density, they can sink or float
• Hot air balloons rise — less dense air provides buoyant force
• Objects feel lighter in water — the buoyant force reduces apparent weight

This calculator works for any fluid — water (1000 kg/m³), seawater (1025 kg/m³), oil (800-950 kg/m³), mercury (13,600 kg/m³), and even air (1.225 kg/m³ at sea level).

How to Use This Calculator

1. Enter Fluid Density: Input the density of the fluid in kg/m³. For water, use 1000 kg/m³; for seawater, 1025 kg/m³; for air, 1.225 kg/m³ (at 15°C).
2. Enter Displaced Volume: Input the volume of fluid displaced by the object in cubic meters (m³). This is the submerged volume of the object.
3. Select Gravity: Choose the gravitational acceleration for the celestial body (Earth, Moon, Mars, or Jupiter) or enter your own value.
4. Calculate: Click the “Calculate Buoyant Force” button or press Enter on your keyboard.
5. Reset: Use the “Reset” button to restore default values (water, 0.5 m³, Earth gravity).
6. Interpretation: The result shows the buoyant force in Newtons (N) and kilogram-force (kgf). For example, an object displacing 0.5 m³ of water experiences a buoyant force of 4,903.33 N (≈ 500 kgf), enough to support a 500 kg mass.