Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
SAC rate (cu ft/min)
0.50
Gas used (cu ft)
53.3
Average ATA
2.67
Planned bottom time at depth (min)
50
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter starting pressure (psi).
- 2Enter ending pressure (psi).
- 3Enter dive time (min).
- 4Enter average depth (ft).
- 5Enter tank capacity (cu ft).
- 6Enter tank rated pressure (psi).
- 7Read your sac rate (cu ft/min) on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
SAC rate normalizes your breathing rate to the surface so you can plan gas at any depth. Educational planning tool, not a substitute for training.
Worked example
Using the values the calculator loads with:
Inputs
- Starting pressure: 3000 psi
- Ending pressure: 1000 psi
- Dive time: 40 min
- Average depth: 55 ft
- Tank capacity: 80 cu ft
- Tank rated pressure: 3000 psi
Results
- SAC rate (cu ft/min): 0.5
- Gas used (cu ft): 53.3
- Average ATA: 2.67
- Planned bottom time at depth (min): 50
What each field means
Inputs
- Starting pressure (psi)
- The starting pressure used in the calculation, measured in psi. Starts at 3000 psi so you have a working example on load.
- Ending pressure (psi)
- The ending pressure used in the calculation, measured in psi. Starts at 1000 psi so you have a working example on load.
- Dive time (min)
- The dive time used in the calculation, measured in min. Starts at 40 min so you have a working example on load.
- Average depth (ft)
- The average depth used in the calculation, measured in ft. Starts at 55 ft so you have a working example on load.
- Tank capacity (cu ft)
- The tank capacity used in the calculation, measured in cu ft. Starts at 80 cu ft so you have a working example on load.
- Tank rated pressure (psi)
- The tank rated pressure used in the calculation, measured in psi. Starts at 3000 psi so you have a working example on load.
Results
- SAC rate (cu ft/min)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Gas used (cu ft)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Average ATA
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Planned bottom time at depth (min)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the scuba air consumption calculator work?
SAC rate normalizes your breathing rate to the surface so you can plan gas at any depth. Educational planning tool, not a substitute for training. The underlying maths is: SAC = (cu ft used ÷ minutes) ÷ average ATA, where ATA = depth/33 + 1.
What do I need to enter?
6 values: starting pressure, ending pressure, dive time, average depth, tank capacity, and tank rated pressure. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the sac rate (cu ft/min) result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary.
Who is this tool for?
It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Scuba Air Consumption (SAC) Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/scuba-air-consumption
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/scuba-air-consumption" target="_blank" rel="noopener">Scuba Air Consumption (SAC) Calculator — RevenueLab</a> (2026).</p>
Source: [Scuba Air Consumption (SAC) Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/scuba-air-consumption) (2026).