Your gas plan is not someone else's problem.
Fast, accurate gas math for air, nitrox, and trimix. Verify your mix. Plan your dive. Own the numbers.
Available now on iOS, iPadOS, macOS, and Android.
Seven tools. Zero guesswork.
Operating Limits
MOD and MinOD for any mix. Know the safe operating range before you get wet.
Equivalent Depths
EAD and END at depth. True nitrogen loading and narcotic potential for your planned profile.
Gas Properties
Density, ppO2, ppN2, and ppHe at any depth. Gas density tracked against breathing resistance limits.
Best Mix
Optimal O2 percentage for your target depth and ppO2 limit. The right mix for the dive you are planning.
Dive Profile Advisor
Multi-segment depth and time profiles with gas switch recommendations. Includes a full-screen dive slate for underwater reference.
Return Number
Thirds, fourths, and sixths rules applied to your starting pressure. Cave and overhead environment gas planning.
Bottom Time
Maximum dive time for your gas supply based on SAC rate, depth, and tank volume. Know your limits before you descend.
No black boxes. No proprietary algorithms.
Transparent Formulas
Tap any result to see the exact equation, source citation, and assumptions behind it. Every formula is open for inspection.
Verified Against Standards
Cross-referenced with published nitrox and trimix reference tables and dive computer firmware.
No Nonsense
No subscription. No ads. No account. A professional tool that respects your time and your intelligence.