Density Converter

Almost exactly 1 g/cm³ at 4 °C, which is 1,000 kg/m³. That is by historical design — the gram was defined from water — rather than a coincidence.

Density relative to water, so it is dimensionless. A specific gravity of 2.5 means two and a half times as dense as water, and anything below 1 floats on it.

Multiply by 1,000. The two units share the same numerical relationship as grams to kilograms and centimetres to metres, which happen to cancel to a factor of a thousand.

Because water expands as it freezes, making ice about 9% less dense than liquid water. It is unusual — most substances contract on freezing — and it is why lakes freeze from the top down.

Yes, for essentially everything. Most materials expand when heated and so become less dense. Water is anomalous below 4 °C, where it expands as it cools further.

It is one of the most straightforward physical tests — measure mass and volume and compare against known values. It is how Archimedes is said to have tested a crown for gold content.

A submerged object displaces its own volume of fluid and experiences an upward force equal to the displaced fluid's weight. Comparing that to the object's weight determines whether it floats.

Osmium, at about 22.6 g/cm³, with iridium essentially tied. A litre of either weighs more than a full domestic gas cylinder.

Because it is less dense — typically 0.85 to 0.95 g/cm³ against water's 1.0 — and because the two do not mix. Both conditions are needed for a stable layer.

Specific gravity readings before and after fermentation show how much sugar was converted to alcohol. The whole ABV calculation rests on a density measurement.

The density of a granular material including the air between the grains, which is far below the material's true density. It is why sand and gravel are sold by bulk density rather than solid density.

Yes — seawater is about 2.5% denser than fresh, which is enough to make floating noticeably easier. The Dead Sea, far saltier again, makes sinking essentially impossible.