Softonic

Density Calculator

Step 1 / 3 Density
Next

Enter an object's mass and its volume and this calculator returns the density using the classic formula ρ = m / V. Results come in both grams per cubic centimetre (g/cm³) and kilograms per cubic metre (kg/m³), so you can compare a sample against reference tables for metals, liquids, woods or minerals. It is handy for chemistry homework, material identification, buoyancy checks and quick lab estimates, no formula sheet required.

How to calculate density

  1. 1

    Measure the mass

    Weigh the object on a balance in grams. Mass is the amount of matter and does not change with location.

  2. 2

    Measure the volume

    Use a measuring cylinder (water displacement) or geometry for the volume in cubic centimetres. 1 cm³ equals 1 mL.

  3. 3

    Read the density

    The tool divides mass by volume and shows the density in g/cm³ and kg/m³ so you can match it to reference values.

The formula

Density is mass per unit volume:

  • ρ = m ÷ V

where ρ (rho) is density, m is mass and V is volume. Rearranged, you can also find mass (m = ρ · V) or volume (V = m ÷ ρ) if you already know the density.

Worked example

A metal cube weighs 270 g and measures 100 cm³. Its density is:

ρ = 270 g ÷ 100 cm³ = 2.7 g/cm³

That matches aluminium, which has a reference density of about 2.70 g/cm³. To convert to SI units, multiply by 1000: 2.7 g/cm³ × 1000 = 2700 kg/m³.

Reference densities

Material Density (g/cm³) Density (kg/m³)
Air (20 °C) 0.0012 1.2
Water (4 °C) 1.000 1000
Aluminium 2.70 2700
Iron 7.87 7870
Lead 11.34 11340
Gold 19.32 19320

A material with a density below 1 g/cm³ floats on water; anything above it sinks. That single comparison is why the density of water (1 g/cm³) is such a useful benchmark.

Pitfalls to avoid

  • Mixed units. Keep mass in grams and volume in cm³ (or mL). Mixing grams with litres or kilograms with cm³ throws the result off by powers of ten.
  • Trapped air. Porous or hollow samples trap air pockets, lowering the apparent density. Submerge fully and tap out bubbles when using water displacement.
  • Temperature. Liquids and gases expand when heated, so density drops as temperature rises. Quote the temperature for precise work.
  • Zero volume. Dividing by a volume of 0 is undefined; the calculator returns 0 until you enter a positive volume.

Frequently Asked Questions

Density equals mass divided by volume: ρ = m ÷ V. Enter mass in grams and volume in cubic centimetres and the result is in g/cm³.

Multiply by 1000. For example, 2.7 g/cm³ × 1000 = 2700 kg/m³. The calculator shows both units side by side.

Compare its density to water (1 g/cm³). A density below 1 g/cm³ floats; a density above 1 g/cm³ sinks. This assumes pure fresh water at about 4 °C.

Use water displacement: note the water level in a measuring cylinder, submerge the object, and the rise in millilitres equals the volume in cm³.

The mass and volume you enter are sent to our server only to compute the density. Your values are not stored or shared, and there are no accounts.

Related Tools

BMI Calculator

Calculate body mass index from height and weight. Shows WHO category, healthy-weight range and limitations of BMI.

Social Security Calculator

Estimate a US Social Security retirement benefit from your PIA and claiming age. Compare monthly and annual amounts at 62, FRA 67 and 70.

Age Calculator

Calculate exact age in years, months and days from a birth date, plus total days, hours and the next birthday countdown.

Dog Age Calculator

Convert your dog's age to human years using modern veterinary research. Breed-size aware: small, medium and large dogs age differently.

Amp-Hour Calculator

Work out battery runtime and stored energy from amp-hours, voltage and load current. Get runtime in hours and minutes plus energy in watt-hours and kilowatt-hours.

Scientific Calculator

Evaluate supported real-number expressions with trig, logs, powers and parentheses locally in your browser.

Tool available in other languages