Combined Gas Law Calculator
Calculate final gas volume using the combined gas law.
Combined Gas Law measurements
Enter your values, then calculate.
Result
How to calculate combined gas law
The combined gas law relates pressure, volume, and temperature for a fixed amount of gas across two states — combining Boyle's and Charles's laws.
How the calculation works
P2 = (P1 × V1 × T2) ÷ (V2 × T1), solved here for a related unknown depending on which variables are given — temperatures must be in Kelvin.
Example
Given P1=2 atm, V1=5L, T1=300K, T2=350K: solving for P2 with V2 held constant would give P2 = (2×5×350)÷(5×300) ≈ 2.33 atm.
Frequently asked questions
How is Result calculated?
Result = [Initial pressure] × [Initial volume] × [Final temperature] ÷ ([Final pressure] × [Initial temperature]).
Is the Combined Gas Law Calculator free to use?
Yes — every calculator on Simple Calculator Tools is free, runs in your browser, and does not require an account.
Combined Gas Law Calculator
P2 = (P1 × V1 × T2) ÷ (V2 × T1), solved here for a related unknown depending on which variables are given — temperatures must be in Kelvin.
Let's understand your combined gas law result.
Calculate a result above and this guide will help you interpret it using this calculator's own formula and explanation.
Pro Tips for Combined Gas Law
- All temperatures must be in Kelvin for this law to work correctly.
- This law assumes a fixed amount of gas (moles) — if gas is added or removed, you need the ideal gas law instead.
Common Combined Gas Law Mistakes to Avoid
- Using Celsius temperatures without converting to Kelvin, which breaks the proportional relationships this law depends on.
When to Use This Calculator
The combined gas law relates pressure, volume, and temperature for a fixed amount of gas across two states — combining Boyle's and Charles's laws.