Comparison

Nitrox Tools vs Oxygen Cylinder Autonomy Calc

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Nitrox Tools

This app provides essential tools for divers to plan and blend enriched air nitrox. It calculates dive parameters like equivalent air depth and maximum operating depth, and supports various blending methods for custom gas mixes. Easily switch between metric and imperial units and save custom settings for frequent use.

Highlights
  • Enriched air nitrox blending
  • Dive planning calculations
  • Equivalent Air Depth (EAD)
  • Partial Pressure of Oxygen (PPO2)
  • Maximum Operating Depth (MOD)
  • Save custom mixes and settings
  • Metric/Imperial unit switching
Features
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Enriched Air Nitrox blending and planning tools in your hand and available at a touch. You can use these tools at your air station to provide the information you need to fill a Nitrox tank from any existing mix (or empty). Dive Planning tools provide your Equivalent Air Depth, PPO2 at your planned depth, Maximum & Contingency Operating Depth at various oxygen partial pressures and the "best mix" for a planned depth and oxygen partial pressure. You can easily switch between Metric and Imperial/U.S. systems of measurement to adapt to a new fill station. The dive planning tools also support both salt and fresh water calculations. Chances are you regularly work with a specific set of mixes and and common dive situations. Nitrox Tools includes the convenience of saved settings that you can recall at a touch and adjust to a new situation as needed. You can also select mix values using pre-installed default mixes or your own saved custom mixes. When updating one of the mixes for a tool you are offered a list of saved mixes that you can use directly or adjust as needed. You can save the currently displayed mix by clicking the "+" button. Just like with the saved calculations, you can re-arrange or delete any mixes in your saved list. Do you need to share your planning or blending calculations with other divers? All the tools have the ability to share the results of the calculations from within the application. You can set default email addresses and a subject within Nitrox Tool's settings that will be automatically added when you share a result. Nitrox Tools supports a number of blending methods: • Top Up - blend a final mix from starting mix and pressure using 100% oxygen and air or any available topping mix. • Bleed Down - save expensive oxygen and valuable time by easily calculating how much gas to bleed from an existing cylinder to switch to a different mix using air or any available topping mix. • Mix + Mix - make a specific final mix using the remaining gas in the cylinder and mixing that with banked Nitrox (rather than pure oxygen) and air or another topping mix. This enables the blending of Nitrox without the use of pure oxygen for certain combinations of mixes. Avoiding pure oxygen may increase the safety of the blending process and help manage the cost. • Top Off - determine the expected result from topping an existing cylinder with air or some other topping mix. This situation is common when a diver wants to have the blender top the mix remaining from the first dive with air from the boat's compressor. Remember you must always personally analyze your mix before diving it. This application is not a substitute for proper training and should not be used as a substitute for proper dive planning or the primary Nitrox blending and planning methods taught during training. Please do not attempt to handle high pressure oxygen or fill SCUBA cylinders without proper training.

About

Oxygen Cylinder Autonomy Calc

Features
Read full description

Must-have App for first aid staff and submarine divers. Calculates the autonomy of the oxygen cylinder and the air cylinder. The first aid personnel will be able to calculate the autonomy of a cylinder of oxygen through the knowledge of its capacity and oxygen supply applied to the patient. Diving enthusiasts will finally be able to easily: - CALCULATE THE LITERS OF YOUR TANK - CALCULATE AIR CONSUMPTION IN A SPECIFIC DEPTH - CALCULATE THE AUTONOMY OF YOUR TANK There is also an All In One section where you will be guided step by step through the entire calculation of your dive, following the order you will find out how many minutes of diving you will have.

Screenshots

Nitrox Tools4 screens
Oxygen Cylinder Autonomy Calc4 screens

Verdict

The call

The clearest difference is price: Oxygen Cylinder Autonomy Calc at Free against Nitrox Tools's $5.99. Oxygen Cylinder Autonomy Calc also leads on update cadence (every 2 months vs every 5 months) and iOS requirement (9.2 vs 15.6). On ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Oxygen Cylinder Autonomy Calc is free to download; Nitrox Tools costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Nitrox Tools ships an update every 5 months, Oxygen Cylinder Autonomy Calc every 2 months. The most recent releases landed on September 23, 2026 and September 13, 2026 respectively.

Scorecard3 real differences · 7 level
Nitrox Tools versus Oxygen Cylinder Autonomy Calc: the parameters behind the verdict, then further details
ParameterNitrox ToolsOxygen Cylinder Autonomy Calc
Price$5.99Free — better
Rating5.0 (4 ratings) — better—
Positive reviews88.5% of reviews—
Number of ratings4 — better—
Update frequencyEvery 5 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS15.69.2 — better
Further details — not scored
Size7 MB16 MB
Age rating4+4+
DeveloperGreg MclaughlinDIGITAL IDEATORS INNOVATIONS SRL

In-app purchases

None

Nitrox Tools

No in-app purchases

None

Oxygen Cylinder Autonomy Calc

No in-app purchases

Questions

Is Nitrox Tools free?
Nitrox Tools costs $5.99, with no in-app purchases.
Is Oxygen Cylinder Autonomy Calc free?
Oxygen Cylinder Autonomy Calc is free to download, with no in-app purchases.
Do Nitrox Tools or Oxygen Cylinder Autonomy Calc have ads?
Neither Nitrox Tools nor Oxygen Cylinder Autonomy Calc shows ads.
Which is updated more often, Nitrox Tools or Oxygen Cylinder Autonomy Calc?
Nitrox Tools ships an update every 5 months, and Oxygen Cylinder Autonomy Calc every 2 months. Most recently, Nitrox Tools was updated on September 23, 2026 and Oxygen Cylinder Autonomy Calc on September 13, 2026.

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