Calculator

Ideal Gas Law Calculator

Solve for gas volume from pressure, amount of substance, and absolute temperature using PV = nRT.

Your inputs

Enter the values

atm
mol
K

Your result will appear here

Complete the fields and choose Calculate. We’ll show the answer and the working.

How to use the Ideal Gas Law Calculator

Solve for gas volume from pressure, amount of substance, and absolute temperature using PV = nRT. Enter the requested values, review their units, and select Calculate. The result panel shows both the answer and the substituted steps.

The formula

V = nRT ÷ P, where R = 0.082057366 L·atm·mol⁻¹·K⁻¹

Frequently asked questions

Why must temperature be in kelvin?

The ideal gas law requires an absolute temperature scale so zero corresponds to the thermodynamic lower limit.

When is the ideal gas law inaccurate?

Real gases can depart from ideal behavior, especially at high pressure, low temperature, or near a phase transition.

Important notes

Results are estimates based on the values supplied and the formula shown. Round only at the end of a calculation, and verify safety-critical, medical, financial, or construction decisions with an appropriate professional.

Editorial details

Reviewed for clarity

Written by Krishna. Last reviewed August 3, 2026.