Gas planning / Calculator 07
Tank Air Volume Calculator
Estimate the amount of surface-equivalent breathing gas in a scuba cylinder at its current pressure.
The numbers / explained
Ready when you are.
Start with the example or enter your own numbers, then calculate.
Every result includes units. All calculations run in your browser.
01 / The calculation
How it works
Imperial: gas volume = rated cubic feet × actual pressure ÷ rated pressure. Metric: gas volume in liters ≈ cylinder water capacity × pressure in bar.
Reference: DAN: Air consumption and gas planning02 / Before you use it
Keep in mind
This is an ideal-gas approximation. Actual gas volume varies with temperature and compressibility at high pressure. Cylinder water capacity (liters) and rated surface gas volume (cubic feet) are different quantities.