Case 1
- Fluid density
- 1000kg/m³
- Displaced volume
- 0.001m³
9.80665N
Open with these valuesBuoyancy Force Calculator
9.80665N
Result: 9.80665 NArchimedes' principle: the upward push equals the weight of the fluid pushed aside, so one litre submerged in fresh water is lifted with 9.80665 N. The answer is a force in newtons, not a displaced mass — it depends on the fluid and the volume, never on what the object is made of.
The numbers at a glance
Held fixed: Fluid density 1,000.000 kg/m³.
| Displaced volume (m³) | Result (N) |
|---|---|
| 0.000000 | 0.00000 |
| 0.000250 | 2.45166 |
| 0.000500 | 4.90333 |
| 0.000750 | 7.35499 |
| 0.001000Your value | 9.80665 |
| 0.001250 | 12.25831 |
| 0.001500 | 14.70998 |
| 0.001750 | 17.16164 |
| 0.002000 | 19.61330 |
Worked examples
Case 2
- Fluid density
- 1025kg/m³
- Displaced volume
- 0.5m³
5,025.90813N
Open with these valuesCase 3
- Fluid density
- 1.225kg/m³
- Displaced volume
- 2m³
24.02629N
Open with these valuesHow it's calculated
F = ρ × g × V
- StepEnter the density of the surrounding fluid in kilograms per cubic metre.
- StepEnter the displaced volume in cubic metres — one litre is 0.001.
- ResultRead the upward force; compare it with the object's weight to see if it floats.
Reference table
| Density, volume | What it is | Buoyant force |
|---|---|---|
| 1.225, 2 | Two cubic metres of air at sea level | 24.0263 |
| 997, 0.05 | Fifty litres in water at 25 °C | 488.8615 |
| 1000, 0.001 | One litre in fresh water | 9.80665 |
| 1025, 0.5 | Half a cubic metre in seawater | 5025.9081 |
| 13534, 0.001 | One litre in mercury | 132.7232 |
Questions
How do I calculate the buoyant force?
Multiply the fluid density by gravity and by the displaced volume: F = ρ × g × V. Kilograms per cubic metre, 9.80665 m/s² and cubic metres give newtons — one litre in fresh water is 1000 × 9.80665 × 0.001 = 9.80665 N.
What is Archimedes' principle?
The upward force on a body in a fluid equals the weight of the fluid the body displaces. It acts straight up against gravity and depends only on the fluid's density and the displaced volume, never on the object's own weight.
Is the buoyant force the same as the object's weight?
No. It is the weight of the displaced fluid, not of the object. This calculator gives only the upward push; to know whether something floats, compare that push with the object's own weight.
How does buoyancy decide whether something floats?
An object floats when the buoyant force reaches its weight and sinks when the weight is larger. In practice that means it floats if its average density is below the fluid's — which is why a steel ship floats and a steel ball does not.
Which density should I use?
Fresh water is about 1000 kg/m³ and 997 at 25 °C, seawater about 1025 because of dissolved salts, and air roughly 1.225 at sea level and 15 °C. Denser fluids lift the same volume harder, which is why floating in the sea is easier than in a lake.
Sources and last check
Information, not professional advice.