Buoyant Force Calculator

Ever wondered why objects float or sink? The answer lies in buoyancy. Our Buoyant Force Calculator helps you find this upward push with clear steps and instant results. Whether you’re a student, a teacher, or just curious, this tool makes physics simple. No long formulas or hard math just type in the numbers and see the solution.

What Is Buoyant Force?

Buoyant force is the upward force that a fluid, like water or air, applies on an object. It’s the reason why a boat floats and a stone sinks. This idea comes from Archimedes’ Principle, which says:

Buoyant Force = Fluid Density × Displaced Volume × Gravity

In short, the heavier the displaced fluid, the stronger the lift.

How Do You Calculate Buoyant Force?

Let’s keep it simple. If you drop an object in water, it pushes water out of the way. That displaced water has weight. The buoyant force is equal to that weight.

Formula:

B = ρ × V × g

Where:

• B = Buoyant Force (in Newtons)
• ρ = Fluid Density (kg/m³)
• V = Displaced Volume (m³)
• g = Gravity (9.807 m/s² on Earth)

How to Use the Buoyant Force Calculator

1. Select the fluid type or enter a custom density.
2. Choose your input method by volume or by mass.
3. Enter your object’s volume or mass with the right units.
4. Set the gravity (default is Earth’s 9.807 m/s²).
5. Click calculate.

The calculator shows the buoyant force in Newtons (N) and also in kgf for easy understanding. It also gives you step-by-step working so you can learn while you solve.

Real World Examples

How much buoyancy does a 200 lb person need?

A person who weighs 200 lb is about 90.7 kg. On Earth, weight = mass × gravity, so:

W = 90.7 × 9.807 ≈ 889 N

To float, the buoyant force must equal this weight. So, the person needs about 889 N of buoyancy.

How much buoyancy does 1 gallon of air have?

One US gallon is about 0.003785 m³. In water (density ≈ 1000 kg/m³):

B = 1000 × 0.003785 × 9.807 ≈ 37.1 N

That’s about 3.8 kgf. So one gallon of air in water can lift about 3.8 kilograms.

Why Our Calculator Helps

Textbooks can confuse you with long steps. Our tool cuts through the clutter. It gives you clear formulas, live results, and worked-out steps in seconds. You don’t need a physics degree to use it.

Final Verdict

Buoyant force is all around us boats, balloons, swimmers. It’s easy to understand when you use the right tool. Our Buoyant Force Calculator with steps makes learning simple and fun. You’ll get accurate answers, real-life context, and a deeper grasp of physics.

FAQs

How do you calculate buoyant force?

Use the formula B = ρ × V × g. Enter the density of the fluid, the volume displaced, and gravity.

Why does an object float?

If buoyant force is greater than the object’s weight, it floats. If it’s less, it sinks.

Can I use this calculator for air?

Yes. Enter the density of air (about 1.225 kg/m³) to calculate buoyancy in air.

Is gravity always 9.807?

On Earth, yes. But you can change it in the calculator for other planets.