SAC Rate Calculator
Calculate your Surface Air Consumption (SAC) rate from any dive. Compare against benchmarks for novice, experienced, and tech divers.
Benchmark: novice 20-25 L/min · experienced 12-16 L/min · technical 10-12 L/min. Imperial: novice 0.7-0.9 cuft/min · experienced 0.4-0.55 · tech 0.35-0.40.
Disclaimer: This tool is an educational aid. It is not a substitute for a personal dive computer, proper certification, or current medical advice. Plan dives conservatively and consult a dive professional when in doubt. Emergency: DAN Asia-Pacific +61-8-8212-9242.
Frequently asked questions
What's a 'good' SAC rate?
Benchmarks: novice 20-25 L/min · experienced recreational 12-16 · technical 10-12 · elite freedivers / instructors 8-10. Imperial RMV: novice 0.7-0.9 cuft/min · experienced 0.4-0.55 · tech 0.35-0.40. Body size and exertion matter — a 90kg diver with 14 L/min SAC has the same gas-efficiency as a 60kg diver with 10 L/min.
Why is my SAC higher on dives with current?
Drag (swimming against current) increases physical effort, which increases CO₂ production, which increases respiratory drive. Expect 30-50% higher SAC on a strong-current dive even at the same depth. Drift diving (with current) brings SAC down again.
Does shallow breathing lower SAC?
No — usually the opposite. Shallow breathing increases CO₂ buildup, which triggers faster, larger breaths. Slow, full breaths (3-4 sec inhale, 3-4 sec exhale, no pause) are most efficient.
How does Nitrox affect SAC calculation?
Not at all — SAC is purely a volume measure. Nitrox doesn't change the air you breathe per minute, only the gas mix composition.