Gas Laws Calculator
Solve Ideal Gas, Boyle's, Charles', Gay-Lussac's, Combined & Dalton's partial pressure — with step-by-step workings
- Using PV = nRT with SI units (Pa, m³, mol, K)
- V = nRT / P
- V = (1 × 8.314 × 273.15) / 101325
- V = 0.0224127 m³
- V = 22.4127 L
What is Gas Laws Calculator?
The Gas Laws Calculator is a science tool designed for students, educators, and engineers who need to solve problems involving the behavior of gases. It covers the five most important gas laws taught in chemistry and physics: the Ideal Gas Law (PV = nRT), Boyle's Law, Charles's Law, Gay-Lussac's Law, and the Combined Gas Law.
Each law describes a specific relationship between pressure, volume, temperature, and the amount of gas. Boyle's Law relates pressure and volume at constant temperature. Charles's Law relates volume and temperature at constant pressure. Gay-Lussac's Law relates pressure and temperature at constant volume. The Combined Gas Law merges Boyle's, Charles's, and Gay-Lussac's laws for scenarios where only the amount of gas is constant. The Ideal Gas Law brings in the number of moles and the universal gas constant R to give a complete picture.
Enter the known values in your chosen units and the calculator will solve for the unknown variable. Unit conversion is handled automatically so you can mix Celsius and Kelvin for temperature, atmospheres and pascals for pressure, and liters and cubic meters for volume. This makes it practical for both textbook problems and real-world science applications.
How to Use Gas Laws Calculator
- Select a gas law
Choose from Ideal Gas Law, Boyle's, Charles's, Gay-Lussac's, or the Combined Gas Law.
- Enter the known values
Fill in the variables you know — pressure, volume, temperature, or moles — along with their units.
- Solve for the unknown
Select the variable you want to find and click Calculate. The result is displayed with unit conversion handled automatically.
- Review the formula used
See the specific formula applied and the substituted values so you can follow the working.
Key Benefits
Covers Ideal Gas Law, Boyle's, Charles's, Gay-Lussac's, and Combined Gas Law all in a single tool.
Accepts multiple units for pressure, volume, and temperature and converts automatically before solving.
Shows the equation used and the values substituted so students can verify and learn from each calculation.
Results are computed immediately in your browser without any page reload or server round-trip.
Frequently Asked Questions
The universal gas constant R is 8.314 J/(mol·K), or equivalently 0.08206 L·atm/(mol·K). The calculator uses the appropriate value based on the units you select.
For gas law calculations, temperature must be in Kelvin. If you enter Celsius, the calculator adds 273.15 automatically. Fahrenheit input is also converted.
The Combined Gas Law (P1V1/T1 = P2V2/T2) relates initial and final states of a fixed amount of gas. The Ideal Gas Law (PV = nRT) relates the absolute state of a gas including the number of moles.
Yes. These laws assume ideal gas conditions — molecules with no volume and no intermolecular forces. Real gases deviate at very high pressures or very low temperatures.