Density Calculator

Density = Mass ÷ Volume, written as D = m/V or ρ = m/V (ρ is the Greek letter rho). If you know any two of the three quantities, you can calculate the third: Mass = Density × Volume (m = ρ × V), and Volume = Mass ÷ Density (V = m/ρ). The SI unit of density is kg/m³, but g/cm³ is commonly used in chemistry and physics (1 g/cm³ = 1000 kg/m³).

Water has a density of exactly 1 g/cm³ (or 1000 kg/m³) at 4°C — the temperature at which it is densest. At room temperature (~20°C) it is very close to 1 g/cm³. This benchmark is fundamental: objects with density less than 1 g/cm³ (cork, wood, oil) float on water, while those above 1 g/cm³ (iron, copper, gold) sink.

Rearrange D = m/V to get m = D × V. Example: a block of aluminum (density 2.71 g/cm³) with volume 500 cm³ has mass = 2.71 × 500 = 1,355 g ≈ 1.36 kg. In the calculator, leave the mass field blank and enter density (2.71 g/cm³) and volume (500 cm³) — it will compute the mass automatically.

Density is a core concept in CBSE Class 8–9 Science (Chapter: Pressure, Buoyancy, and Archimedes' Principle). The formula ρ = m/V links mass, volume, and the substance's nature. Common exam questions ask: why does ice float on water (ice ≈ 0.92 g/cm³, less than water 1.0 g/cm³), or which of two objects is heavier given the same volume. The density reference table in this calculator lists common materials exactly as they appear in NCERT textbooks.