Tools
Dive calculators
Free calculators for no-deco limits, nitrox and trimix mixes, gas planning and oxygen exposure.
Nitrox & Trimix
Nitrox Calculator
Nitrox & TrimixMaximum operating depth (MOD), best mix and equivalent air depth (EAD) for enriched air nitrox.
Open toolNitrox Blending Calculator
Nitrox & TrimixHow much oxygen and air to add for a nitrox fill, from an empty cylinder or with gas already in it.
Open toolTrimix Calculator
Nitrox & TrimixOperating depth range, equivalent narcotic depth (END), best mix and partial-pressure blending for helium mixes.
Open toolCNS / OTU Calculator
Nitrox & TrimixCNS clock percentage and OTU (oxygen tolerance unit) accumulation based on oxygen partial pressure (ppO₂).
Open toolGas Planning
SAC Calculator
Gas PlanningWork out your surface air consumption (SAC) in L/min from the pressure, time and depth of a logged dive.
Open toolRMV Calculator
Gas PlanningConvert a SAC rate in bar/min to RMV in L/min and back, so your breathing rate works with any cylinder size.
Open toolGas Planning
Gas PlanningGas required for a dive, minimum reserve (rock bottom) and turn pressure by the rule of thirds.
Open toolTank Duration Calculator
Gas PlanningHow many minutes your gas lasts at a given depth, from your SAC rate, tank size and the pressure you keep in reserve.
Open toolDecompression & Tables
DECO 2000 Table
Decompression & TablesThe dive table used in CMAS training: no-deco limits, group letters and surface interval credits.
Open toolDECO 2000 Planner
Decompression & TablesEnter depth and time to get the dive profile, deco stops and group letter. Works for repetitive dives too.
Open toolUS Navy Dive Tables
Decompression & TablesThe Rev 7 air tables in feet: no-stop limits, group letters, surface interval credit, residual nitrogen and decompression stops.
Open toolUS Navy Dive Planner
Decompression & TablesNo-stop limit, group letter and decompression stops from the US Navy tables, for single and repetitive dives in feet or meters.
Open toolNDL Calculator
Decompression & TablesThe no-decompression limit for a depth and gas: Bühlmann ZHL-16C with gradient factors, the US Navy table and DECO 2000.
Open toolMulti-Gas Deco Planner
Decompression & TablesDecompression stops for air, nitrox or trimix with up to two deco gases, from the Bühlmann ZHL-16C model with gradient factors.
Open toolAltitude Diving Calculator
Decompression & TablesAir pressure at a mountain lake, the sea-level equivalent depth to use with tables, and adjusted stop depths.
Open toolNo-Fly Time Calculator
Decompression & TablesHow long to wait before flying after diving: the DAN minimum of 12, 18 or 24 hours and your earliest takeoff time.
Open toolWeighting
Conversions
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These tools are educational planning aids; they are not a substitute for dive training, current printed tables or a dive computer. Verify results against your training and always plan within the limits of your certification.