What is the Boyle's Law Calculator?
Boyle's law states that for a fixed amount of gas at constant temperature, pressure and volume are inversely proportional: P₁V₁ = P₂V₂. Enter any three of initial pressure, initial volume, final pressure, and final volume — this calculator solves the fourth. Supports atm, kPa, mmHg, Pa for pressure and L or mL for volume. Also shows pressure and volume ratios. Runs instantly in your browser with no signup.
How to use the Boyle's Law Calculator
- Choose which variable to solve: P₂, V₂, P₁, or V₁.
- Enter the three known values.
- Select pressure and volume units.
- Read the solved value and P₁/P₂ and V₂/V₁ ratios.
- Copy the summary for homework or lab notes.
Common use cases
- Finding final pressure when a gas expands from 1 L to 2 L at constant T
- Calculating compressed volume when pressure doubles
- Checking P₁V₁ = P₂V₂ in introductory gas law homework
Frequently asked questions
- What is Boyle's law?
- P₁V₁ = P₂V₂ at constant temperature and fixed moles of gas. If volume doubles, pressure halves.
- When does Boyle's law apply?
- For ideal gases at constant temperature with no change in amount of gas. Real gases approximate this at moderate pressure.
- How is Boyle's law related to the ideal gas law?
- Boyle's law is the special case of PV = nRT when n and T are constant, so PV stays constant.
- Can I mix pressure units?
- Use the same pressure unit for P₁ and P₂. The calculator converts internally for accurate results.
