What this calculator does
Boyle's Law works out pressure or volume of a fixed gas amount after an isothermal change, from the other values. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
Formulap1·V1 = p2·V2 (constant temperature)
The inputs explained
| Field | What to enter |
|---|---|
| Initial pressure (p1) (kPa) | A number, measured in kPa. Starts at 101.325. |
| Initial volume (V1) (L) | A number, measured in L. Starts at 2. |
| Solve for | Choose from Final pressure (p2), Final volume (V2). |
| Known final value (V2 if solving p2; p2 if solving V2) (L or kPa) | A number, measured in L or kPa. Starts at 1. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with initial pressure (p1)
Every other input is held at the calculator’s starting values while initial pressure (p1) varies. Select any row to load that scenario into the calculator.
How the answer changes with initial pressure (p1)