About the Ideal Gas Law Calculator
What is the Ideal Gas Law Calculator?
The ideal gas law PV = nRT describes most gases well at ordinary temperatures and pressures. This calculator solves for whichever quantity you need.
Enter a molar mass to also get the mass of gas and its density.
How to use the Ideal Gas Law Calculator
- Find (sample: Volume V)
- Pressure (kPa) (sample: 101.325)
- Volume (L) (sample: 22.4)
- Amount (mol) (sample: 1)
- Temperature (°C) (sample: 0)
- Molar Mass (g/mol, optional, for grams) (sample: 28.97)
- Press Solve PV = nRT (results also refresh as you type). The result card shows the Result, along with Pressure, Volume, Amount and Temperature.
Formula used
P × V = n × R × T
- R = 8.314 J/(mol·K) = 8.314 kPa·L/(mol·K)
- T = temperature in kelvin
Real gases deviate at high pressures and low temperatures.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Find | Volume V |
| Pressure (kPa) | 101.325 |
| Volume (L) | 22.4 |
| Amount (mol) | 1 |
| Temperature (°C) | 0 |
| Molar Mass (g/mol, optional, for grams) | 28.97 |
| Result | Value |
|---|---|
| Result | 22.414 L |
| Pressure | 101.325 kPa |
| Volume | 22.414 L |
| Amount | 1 mol |
| Temperature | 273.15 K |
| Mass of gas | 28.97 g |
| Density | 1.2925 g/L |
Tips for using the Ideal Gas Law Calculator
- At 0 °C and 1 atm, one mole of any ideal gas occupies 22.414 L.
- At 25 °C and 1 bar, the molar volume is about 24.8 L.