# Immersed Weight Calculator

URL: https://speedycalculator.com/calculators/physics/immersed-weight/
Last updated: 2026-10-30

> The immersed weight calculator finds the apparent weight of an object submerged in various liquids – water, seawater, oil, mercury and more – from its weight in air and its volume.

## Inputs

- Mass in air (kg, g, mg, t, lb, oz)
- Volume (L, mL, m³, US gal, ft³)

## Results

- Object density
- Apparent mass in fresh water
- Apparent mass in seawater
- Apparent mass in ethanol
- Apparent mass in gasoline
- Apparent mass in olive oil
- Apparent mass in glycerine
- Apparent mass in mercury

## Formula

```
W_immersed = W_air − ρ_liquid·g·V
```

## Explanation

Objects feel lighter underwater because the liquid pushes up on them. Divers, salvage crews and anyone lifting things from a pool experience this. In mercury, even iron floats.

### How to use the Immersed Weight Calculator

- **Mass in air**
- **Volume**

Results update as you type, every field has its own unit menu, and everything is calculated in your browser.

### How it works

Enter the object's weight (mass) in air and its volume.

### Inputs explained

FieldWhat to enterMass in airUnits: kg, g, mg, t, lb, ozVolumeUnits: L, mL, m³, US gal, ft³

### What each result means

- **Object density** = [Mass in air]÷[Volume]
- **Apparent mass in fresh water** = [Mass in air] - 998.2×[Volume]
- **Apparent mass in seawater** = [Mass in air] - 1025×[Volume]
- **Apparent mass in ethanol** = [Mass in air] - 789×[Volume]
- **Apparent mass in gasoline** = [Mass in air] - 745×[Volume]
- **Apparent mass in olive oil** = [Mass in air] - 911×[Volume]
- **Apparent mass in glycerine** = [Mass in air] - 1261×[Volume]
- **Apparent mass in mercury** = [Mass in air] - 13534×[Volume]

### Example values

How the main result changes when **Mass in air** changes and everything else stays at the example values above:

Mass in air (kg)Apparent mass in fresh water (kg)53.73237.56.2323108.732312.511.23231513.73232018.7323

## Worked example

Inputs — Mass in air: 10 kg; Volume: 1.27 L.

Results — Object density = 7,874.01575 kg/m³; **Apparent mass in fresh water = 8.73229 kg**; Apparent mass in seawater = 8.69825 kg; Apparent mass in ethanol = 8.99797 kg; Apparent mass in gasoline = 9.05385 kg; Apparent mass in olive oil = 8.84303 kg; Apparent mass in glycerine = 8.39853 kg; Apparent mass in mercury = -7.18818 kg.

## Key terms

- **Apparent weight**: Weight minus buoyant force.

## FAQ

**Why does a negative value appear?**
The object would float – the liquid can support more than its weight.

**Why does iron float in mercury?**
Mercury is denser than iron.

**Is apparent mass the same as true mass?**
No – true mass doesn't change; only the supporting force does.

**How do divers use this?**
Weight belts are chosen to give slightly negative buoyancy.


## Sources

- [OpenStax – University Physics Volume 1](https://openstax.org/details/books/university-physics-volume-1)
- [HyperPhysics (Georgia State University)](http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html)