What Boyle’s Law describes
Boyle’s Law states that for a fixed amount of gas held at constant temperature, pressure and volume are inversely related: as one goes up, the other goes down proportionally. This is written as P1 × V1 = P2 × V2.
How this calculator works
Enter the initial pressure and volume of your gas sample, choose whether you want to solve for the final pressure or final volume, and enter the known final value. The calculator rearranges P1V1 = P2V2 to find the missing quantity, assuming temperature and the amount of gas do not change between the two states.
Boyle’s Law is an idealized model that works well for many gases under normal laboratory conditions. It becomes less accurate at very high pressures or very low temperatures where real gas effects appear. This tool is for general educational and planning purposes.