About the Density Converter
Density is mass divided by volume, and the number you get depends entirely on which mass unit and which volume unit the source used. A materials datasheet may quote 7.85 g/cm3 for steel while a structural table for the same alloy says 490 lb/ft3. Both describe the identical material, and this converter moves between the fourteen units those documents draw on.
A helpful anchor is water at 4 degrees Celsius, close to 1000 kg/m3, 1 g/cm3, 1 kg/L and 62.4 lb/ft3 all at once. That equivalence is why the metric side feels tidy: a gram per cubic centimetre and a kilogram per litre are the same quantity written two ways, and a gram per litre matches a milligram per millilitre, which is the form clinical results use. The imperial side has no such luck, since a cubic foot holds 1728 cubic inches and a US gallon is 231 cubic inches.
Pound per US gallon is included because fuel, paint and chemical shipping papers still use it, and it is easy to confuse with the imperial gallon version. Slug per cubic foot appears for anyone reading older aerodynamics texts. Enter as many values as you like, one per line. If you only need the mass side of the calculation, open the Mass Converter.
How to use
- Paste the density figures, one number per line.
- Select the unit printed on your datasheet under From.
- Select the unit your calculation needs under To.
- Set Rounding to keep the output tidy, then copy it.
Common questions
- What is the density of water in these units?
- Roughly 997 kg/m3 at room temperature, which is 0.997 g/cm3 or about 62.2 lb/ft3.
- Is g/cm3 the same as kg/L?
- Yes, they are numerically identical, because a litre is 1000 cubic centimetres and a kilogram is 1000 grams.
- Which gallon does pound per gallon use?
- The US liquid gallon of 3.785411784 litres. Convert to litre based units first if your source uses the imperial gallon.
- Can I convert specific gravity with this?
- Specific gravity is a ratio with no units. Multiply it by 1000 to get kg/m3 first, then convert that figure here.