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The diver’s toolkit

Nitrox calculations, deco planning, buoyancy — everything you need on the boat or at the fill station.

Try the Nitrox calculator

All tools

21 available · 3 coming soon
Nitrox CalculatorNitrox

Nitrox Calculator

MOD, EAD, best mix and CNS toxicity. Everything you need to plan an enriched air dive.

MODEADPPO₂CNSEANx
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↧
MOD

Maximum depth (MOD)

Your mix and your ppO2 limit: the depth you must never exceed, at sea, in a lake or at altitude.

MODppO₂max depth
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O₂
PpO2

PpO2 on the bottom and at stops

Your mix’s oxygen partial pressure on the bottom and at the stops, with your max depth.

ppO₂stopsDalton
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≈
EAD

EAD: equivalent air depth

The depth to read in your air table with nitrox, and the MN90 row to use.

EADMN90nitrogen
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%
Best mix

Best mix

The richest nitrox for your depth and ppO2, and the club mix to take.

best mixMODCNS
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⚖
Weighting

Dive weighting

Changing cylinder or water: the lead to add or remove, and a starting estimate.

weightcylinderfresh / sea
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O₂
CNS %

CNS % of a dive

Your dive's CNS % on the NOAA table, stops and deco gas included, and your max bottom time.

CNSNOAAO₂ toxicity
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⏲
CNS interval

CNS interval: when to dive again

Your CNS on surfacing and your target: how long to wait and when to dive again.

CNSintervalhalf-life
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½
CNS reduction

CNS reduction

Your CNS on surfacing and your interval: the residual CNS at the start of the next dive.

residual CNShalf-liferepetitive dive
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🫁
OTU

OTU: pulmonary oxygen toxicity

The oxygen dose your lungs take, over one dive, one day or several days.

OTUREPEXlungs
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⛰
Altitude

Altitude diving

In a mountain lake: the depth to read in your table, your real stops and your ascent rate.

altitudeMN90Chauvin
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He
END

END: narcosis and density

The equivalent narcotic depth of your nitrox or trimix, gas density and the ideal mix.

ENDtrimixnarcosis
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Tx
Trimix

Trimix blend

The bottom trimix to order for your depth, ppO2 and END, density included.

trimixheliumdensity
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🌊
Tide

Tidal currents

The current during your dive, the next slack water and the calm windows of the day.

currentslackcoefficient
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🌡️
Cold

Heat balance

The heat you lose during your dive, your body temperature drop and the protection to choose.

coldwetsuitdrysuit
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⚙️
Compressor

Compressor payback

Cost per fill, break-even point and years to pay back the purchase.

fillcostclub
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⇄
Pressure & Depth

Pressure & Depth Converter

Instant conversions: bar ↔ psi, metres ↔ feet, absolute pressure ↔ depth, fresh vs salt water.

barpsidepthpressure
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💨
Air consumption

Air Consumption Calculator

Work out your SAC rate, see how depth affects your air consumption and compare how long your cylinder lasts.

SACL/mingas timecylinder
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🧪
Gas blending

Gas Blender

Cylinder, target mix and available gases: partial pressure blending steps to read on the gauge.

partial pressurepure O2bankscascade
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🏷️
Analysis

Nitrox Label

Analyse your cylinder and fill in its label step by step: mix, max depth, pressure, initials.

analysisMODlabelfill log
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N₂
Theory

Nitrogen saturation

Play a dive and watch nitrogen enter your body at depth, then leave as you ascend. Bühlmann model.

nitrogenoff-gassingBühlmann12 m
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⏱
Coming soon

Decompression Planner

Deco stops, ascent time, optimised dive profile.

deco stopsGFBühlmann
🫧
Coming soon

Volume & Pressure Converter

Bar, PSI, litres, cu.ft — every dive conversion you need.

barpsitank volume
📋
Coming soon

Quote Generator

Create and send professional quotes in seconds. Perfect at dive shows or in the shop to build a live quote with your centre’s details.

quotedive showcentreinvoicing

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