Buoyancy Calculator
Floats, sinks, or hangs exactly where you put it.
Floats, sinks, or hangs exactly where you put it. Enter fluid density, object volume and object mass for the buoyant force and the verdict.
1 litre is 0.001 m³.
Buoyant force
9.807 N
Floats — buoyancy exceeds weight
Archimedes' principle: the buoyant force equals the weight of fluid displaced. There are three outcomes, not two — denser sinks, less dense floats, and exactly equal density is neutrally buoyant and stays wherever it is put. That third case is what a submarine trims for and what a fish's swim bladder adjusts continuously. A floating object settles with the fraction of itself submerged equal to the density ratio, which is why about 90% of an iceberg is underwater.
How the Buoyancy Calculator works
Enter fluid density, object volume and object mass for the buoyant force and the verdict. There are three outcomes rather than two — equal density gives neutral buoyancy, which is what a submarine trims for.
Also known as: archimedes principle calculator · buoyant force calculator · will it float calculator · displacement calculator
Where to go next
The Buoyancy question rarely arrives on its own. These are the ones that usually come with it:
- Hydrostatic Pressure Calculator — P = ρgh, in gauge and absolute.
- Specific Gravity Calculator — Density as a ratio, plus the API petroleum scale.
- Density Calculator — Density, mass or volume, and whether it floats.
- Speed Distance Time Calculator — Any one of the three from the other two, in four units.
Frequently asked questions
What is Archimedes' principle?
The buoyant force on an object equals the weight of the fluid it displaces. That is the whole of it, and it holds whether the object floats, sinks or hovers.
Why do steel ships float?
Because a hull encloses a large volume of air, so the ship's average density is well below water. Steel sinks; a steel shell full of air does not.
What is neutral buoyancy?
Equal density to the fluid, so buoyancy and weight cancel and the object stays wherever it is placed. Submarines trim ballast to reach it, and fish adjust a swim bladder continuously.
How much of an iceberg is underwater?
About 90%. A floating object sits with the fraction of itself submerged equal to the ratio of its density to the fluid's, and ice is roughly 0.92 that of seawater.
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Related calculators
Hydrostatic Pressure Calculator
P = ρgh, in gauge and absolute.
OpenSpecific Gravity Calculator
Density as a ratio, plus the API petroleum scale.
OpenDensity Calculator
Density, mass or volume, and whether it floats.
OpenSpeed Distance Time Calculator
Any one of the three from the other two, in four units.
Open