What this calculator does
Terminal velocity works out maximum falling speed once drag balances gravity. 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
Formulav_t = √(2mg / (ρ·A·C_d))
The inputs explained
| Field | What to enter |
|---|---|
| Mass (kg) | A number, measured in kg. Starts at 80. |
| Fluid density (air ≈ 1.225) (kg/m³) | A number, measured in kg/m³. Starts at 1.225. |
| Cross-sectional area (m²) | A number, measured in m². Starts at 0.7. |
| Drag coefficient | A number. 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 mass
Every other input is held at the calculator’s starting values while mass varies. Select any row to load that scenario into the calculator.