Boyle's Law
Also known as P₁V₁ = P₂V₂ · pressure volume law
Enter your known values, leave one input blank, and solves for the missing one. Try different units for next level excitement!
Learning zone
Robert Boyle published his gas law in 1662, making it one of the oldest quantitative laws in physics: at constant temperature, the pressure and volume of a trapped gas are inversely proportional, so their product never changes. Cap a syringe and squeeze — compress 60 mL of air at 100 kPa down to 20 mL and the pressure climbs to 300 kPa. Molecularly, shrinking the space raises how often molecules hammer the walls, and pressure rises in exact proportion.
The law matters wherever gas gets squeezed. Scuba divers learn it first: air breathed at depth expands as they ascend, which is why the cardinal rule is never to hold your breath on the way up. Boyle's law assumes the temperature and the amount of gas stay fixed; change either and you need Charles's law or the combined gas law instead.
- = Initial pressure
- = Initial volume
- = Final pressure
- = Final volume
- Initial pressure — Gay-Lussac's Law, Combined Gas Law
- Initial volume — Charles's Law, Combined Gas Law
- Final pressure — Gay-Lussac's Law, Combined Gas Law
- Final volume — Charles's Law, Combined Gas Law