DiverInterCom KCore Scuba · Dive Calculators

Gas Management Calculator

Plan open-circuit gas across descent, bottom time, ascent, travel segments and user-defined safety/decompression stops. Stops may remain on backgas or switch to Stage 1 / Stage 2; once a stage is selected at a stop, it becomes the active gas for the following ascent until another source is selected.

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Dive Inputs

Metric calculation using litres, bar, metres and RMV in litres per minute.

Backgas cylinder sizeInternal water volume in litres.

Start pressureBackgas pressure at dive start.

Minimum pressure leftPlanned backgas reserve after the dive.

RMVSurface respiratory minute volume in L/min.

Maximum / bottom depthPlanned maximum depth in metres.

Default descent rateUsed between surface, travel segments and bottom depth.

Default ascent rateUsed between bottom, stops and surface.

Travel In

Optional constant-depth travel on the way to the dive site. Example: descend to 5 m, swim 3 minutes over the reef, then continue down the wall.

Travel Out

Optional constant-depth travel on the way back. It is placed at its actual depth during ascent and uses the gas source active at that point.

Safety / Decompression Stops

Enter only stop depth, stop time and gas source. Stops are executed in deepest-to-shallowest order.

Stage pressure settings

Stage start pressureUsed for Stage 1 and Stage 2 sizing.

Stage minimum pressurePressure intentionally remaining in each stage.

Gas Plan

The calculator deducts Travel In, descent, ascent, Travel Out and backgas stops first. Remaining usable backgas determines the available bottom time.

Calculated bottom time

—min

Total runtime

—min

Usable backgas

—L

Non-bottom backgas use

—L

Bottom gas rate

—L/min

Backgas remaining

—bar

Profile Gas Breakdown

Phase	Depth	Time	Source	Gas

Dive Profile / Gas Source

Actual Travel In, descent, bottom, ascent/stops and Travel Out from the current plan.

Line colour shows the active gas source. Travel In appears near the beginning, Travel Out at its actual point on the return, and stops remain at their entered depths.

Travel gas: changing-depth segments use the average ambient pressure between start and end depth. Constant-depth travel and stops use ambient pressure at that depth. Stage sizing is calculated from the gas assigned to each stage and the entered stage pressure window.

This is a gas-management planning aid, not a decompression model. Stop depth/time are user inputs; the calculator does not determine whether decompression is required or whether a chosen gas is breathable/appropriate at a given depth.

Educational planning aid only. This calculator is not a substitute for formal training, an appropriate dive plan, recognized gas-management procedures, manufacturer guidance, or a properly configured dive computer. Real dives must include appropriate ascent, reserve and contingency planning for the dive being conducted.