Free Tool
Set your altitude, ambient and fill temperatures, configure your banks (O₂, He, Air, with optional volume/pressure tracking), then save a named cylinder for every customer or buddy. Dive Kit returns a numbered fill plan: bleed, add He, add O₂, top with air, with the resulting mix and total gas drawn from each bank. Running a mixing panel instead? Continuous mode computes the flow ratios for your rotameters and the readings to expect on the in-line analyzers.
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Two blending modes: a numbered partial-pressure plan, or flow ratios for a continuous panel.
The Blend Planner is built for the way fill stations actually work. The Environment card sets altitude, ambient temperature, and fill temperature so the math accounts for thermal compression after the cylinder cools. The Banks card lists every gas source you have available, Air, O₂, He, or any custom bank, each with optional volume@pressure tracking so you know how much each fill drains from your supply.
The Cylinder card holds the current cylinder's volume, current pressure, residual O₂%/He%, and the target mix and pressure. Quick Fill loads from your saved gas presets. The horizontal cylinder bar at the bottom lets you save and switch between named cylinders, "Bob", "Charlie", "Ronny", so you can line up the day's fills upfront and work through them without losing any configuration. Banks and environment are shared across all cylinders.
The Plan output is a numbered sequence: bleed to a target pressure, add He to a pressure, add O₂ to a pressure, top with Air. Each step explains what changes ("O₂% Change: 1.9% → 48.5%") so you can stop mid-fill and verify with an analyzer. The Result card shows the final mix (e.g. TMX 32/20) at target pressure and the total gas drawn from each bank in litres and bar.
Continuous mode plans for shops that blend gas as it flows into the cylinder. The panel feeds are fixed (Air, O₂, and He metered into the air intake), so you only set the cylinder's current and target state. The output gives the blend the panel must produce in the fill line, the Air, O₂, and He flow ratios for setting the rotameters, and the O₂ readings to expect on the in-line analyzers. A Gas Injection Order toggle matches the intermediate reading to He-first or O₂-first panel layouts. To our knowledge, no other dive app plans continuous blends.
It works in absolute pressure and corrects for fill temperature and altitude, so the cylinder settles at the mix and pressure you planned once it cools. Saved cylinders, banks, and environment persist across app restarts.
Partial pressure blending relies on Dalton's Law: each gas contributes independently to the total pressure, so you add gases sequentially, first helium, then oxygen, then top off with air. Dive Kit works in absolute pressure and corrects for fill temperature and altitude, so the cylinder settles at the mix and pressure you planned once it cools. Continuous-flow blending holds the mix constant in a flowing line instead: the planner solves the Air, O₂, and He fractions of total flow that produce the target blend, and predicts the analyzer readings along the line. Both modes assume ideal gas behaviour, accurate to within a few percent at normal fill pressures, and neither replaces analysing the finished mix.
Two blending modes: a numbered partial-pressure plan, or flow ratios for a continuous panel.
Environment & Banks
Set altitude, ambient temperature, and fill temperature so the math accounts for thermal compression after the cylinder cools. The Banks card lists every gas source with optional volume@pressure tracking, so you always know how much each fill drains from your supply.
Multi-cylinder management
The horizontal cylinder bar lets you save and switch between named cylinders, "Bob", "Charlie", "Ronny", without losing any configuration. Each cylinder keeps its own current pressure, residual mix, and target. Quick Fill loads from your saved gas presets. Banks and environment are shared across all cylinders.
Step-by-step plan
Dive Kit returns a numbered fill plan: bleed to a target, add He, add O₂, top with air. Each step shows the resulting O₂% and He% change so you can stop mid-fill and verify with an analyzer. The Result card confirms the final mix at target pressure and the total gas drawn from each bank.
Continuous-flow blending
Run a continuous blending panel? Switch to Continuous mode and Dive Kit plans the flow instead of the pressure steps: the blend the panel must produce in the fill line, the Air, O₂, and He ratios to set on your rotameters, and the O₂ readings to expect on the in-line analyzers. A Gas Injection Order toggle matches the intermediate reading to He-first or O₂-first panel layouts. To our knowledge, no other dive app plans continuous blends.
More free dive planning tools in Dive Kit.
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