💨 Ideal Gas Law
PV = nRT — solve for any variable
About this calculator
The Ideal Gas Law links pressure, volume, temperature, and the amount of gas in one equation. Enter any three of pressure, volume, moles, and temperature and the calculator solves for the fourth, handling unit conversions between atmospheres, pascals, litres, and Celsius or Kelvin automatically.
PV equals nRT, where R is the gas constant (8.314 J/mol·K). The law assumes gas particles have no volume and never interact — a good approximation for real gases at ordinary pressures and temperatures, breaking down near condensation points.
Tip: Always convert Celsius to Kelvin first (add 273.15). Forgetting this is the classic error — 0°C is 273.15 K, and the formula needs the absolute scale.