The ideal gas law, PV = nRT, connects the pressure, volume, amount and temperature of a gas. Choose which one you want to find, enter the other three, and this calculator solves the equation.
Enter pressure in atmospheres, volume in litres and temperature in degrees Celsius (it is converted to kelvin for you). Real gases follow the law closely at low pressure and high temperature.
| Find | Volume (V) |
| Pressure (P) | 1 atm |
| Amount of gas (n) | 1 mol |
| Temperature (T) | 0 °C |
| Pressure (atm) | 1 |
| Pressure (kPa) | 101.325 |
| Volume (L) | 22.414 |
| Amount (mol) | 1 |
| Temperature (K) | 273.15 |
| Temperature (°C) | 0 |
One mole of an ideal gas occupies 22.414 L at 0 °C and 1 atm.
Try this example →| Find | Pressure (P) |
| Volume (V) | 10 L |
| Amount of gas (n) | 20 mol |
| Temperature (T) | 25 °C |
| Pressure (atm) | 48.9308 |
| Pressure (kPa) | 4,957.91 |
| Volume (L) | 10 |
| Amount (mol) | 20 |
| Temperature (K) | 298.15 |
| Temperature (°C) | 25 |
20 mol of gas in a 10 L cylinder at 25 °C is at 48.9308 atm.
Try this example →PV = nRT, the equation of state of an ideal gas.
0.0821 L·atm/(mol·K), or 8.314 J/(mol·K).
Gas volume and pressure are proportional to absolute temperature; on the Celsius scale zero isn't the true zero.
At low pressure and high temperature, when molecules are far apart and attract each other very little.