About the Ideal Gas Law Calculator
Solves PV = nRT for pressure, volume, moles, or temperature.
What it is
Enter any three of P, V, n, T in whichever units you have. Values are converted internally to atm, L, and K, solved with R = 0.0821 L·atm/(mol·K), then converted back to your chosen output unit.
Features
Solve for any variable
Pressure, volume, moles, or temperature.
Multi-unit support
Automatic conversion across common units for each quantity.
Absolute-zero validation
Temperatures below 0 K are rejected.
STP shortcut
One click sets 0°C and 1 atm.