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Density Calculator

By Mateusz Mucha and Steven Wooding
Last updated: Sep 18, 2020

The density calculator will help you estimate the relationship between the weight and volume of an object. This value, called density, is one of the most important physical properties of an object. It's also easy to measure.

If you want to know how to find density, keep reading. This article will provide you with the density formula, which this calculator is based on. You'll also learn how the density of water changes under different circumstances.

We will deal with these questions:

How to find density

  1. Determine the weight of an object. For example, a glass of water weights 200 grams net (not including the glass).
  2. Find out the volume of an object. In our example, it's 200 cm3.
  3. Divide weight by volume. 200 g / 200 cm3 = 1 g/cm3
  4. Optionally, change the unit. 1 g/cm3 = 1 (1/1000 kg) / (1/1000000) m3 = 1000 kg/m3

Or you can use our density calculator to make it a breeze!

The fastest way to find the density of an object is of course to use our density calculator. To make the calculation, you'll need to know a few other values to start with. Make a note of the object's weight and volume. After typing these values into the density calculator, it will give you the result in kilograms per cubic meter.

If all you need is to convert between different units, just click on the units for density and select your desired units from the list. If your unit is not thee, you can use our density conversion calculator. If you plug in your result there, the tool will convert it into:

  • kilograms per cubic decimeter
  • pound per cubic foot
  • pound per cubic yard
  • pound per US gallon

Sometimes people are looking to convert grams into cups. If you know the density of the product as well as its weight in grams, you can find the volume of the ingredient in cups.

Allow us to throw in a bit of a curve ball here by reminding you that if you want to calculate the density of pixels on your screen, this is not the calculator your looking for, try this one.

Density formula

Another way to calculate the weight to volume ratio of an object is to use the density formula. The calculation is not too complicated as you only need to do one operation to find it.

The density formula is as follows:

D = m / v


  • D - density

  • m - mass

  • v - volume

Density of water

For most purposes, it's enough to know that the density of water is 1000 kg/m3. However, as with almost all materials, its density changes with temperature. However, we have a slight, but a super important anomaly when it comes to water. While the general rule is that as temperature goes up, the density lowers, water behaves differently between 0 °C and 4 °C.

If you cool water from room temperature, it becomes increasingly dense. However, at approximately 4 °C degrees, water reaches its maximum density. How's this important? It makes it much harder for lakes to freeze completely in the winter. Since the water at 4 °C is the heaviest, it falls to the bottom of the lake. The colder water stays at the surface and turns to ice. This phenomenon, coupled with a low thermal conductivity of ice, helps the bottom of the lake stay unfrozen, so that fish can survive. It is this same principle that scientists think helped life get started on Earth. If water froze from the bottom up, then life never would have gotten the chance.

There are also other aspects which affects water's density. It changes slightly whether it is tap, fresh or salt water. Every dissolved particle inside a body of water affects its density.

Mateusz Mucha and Steven Wooding