In the 1960s, Anton Paar introduced a new method of density measurement based on the law of harmonic oscillation. The accuracy and versatility of this "oscillating U-tube principle" has since made it the standard method of density measurement worldwide.

Density is the relationship "mass per unit volume" of a substance. The most commonly derived reading from density is specific gravity, which, though dependent on temperature and reference material, can be loosely defined as the measured density divided by the density of water. Various concentrations can be calculated from the density and specific gravity.

Anton Paar provides highly accurate laboratory instruments for a variety of requirements and budgets, from portable density meters to high resolution R&D instruments.