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Model gas use for a depth-and-time profile with a selected pressure allocation. Cross-check minimum gas and every other dive limit separately.
Allowed range: 5 to 50 L/min.
Check whether the entered supply covers both depth and bottom time.
Defaults are suitable for a typical plan. Adjust them to match your training and conditions; this browser remembers your last-used rates for the next plan.
Allowed range: 6 to 30 m/min.
Allowed range: 3 to 18 m/min.
Allowed range: 5 to 20 L.
Allowed range: 170 to 240 BAR.
Fixed pressure allocation of 50 BAR. It is not a universal minimum-gas calculation; confirm a reserve for the actual dive and team.
Gas model only
+5 min
longer
3,133 L
Does not cover scenario
+5 m
deeper
3,338 L
Does not cover scenario
Both
+5 m & +5 min
3,688 L
Does not cover scenario
This planner models gas use from breathing rate, depth, time, and transit assumptions. It compares the modeled demand with the supply above your selected pressure allocation; it does not authorize a dive or time at depth.
Solve time uses the same profile algebraically. Solve depth searches from the surface to 100 m and rounds a gas-limited result down to a whole m; reaching that upper bound is reported separately.
Your RMV (Respiratory Minute Volume) or SAC (Surface Air Consumption) rate is how much gas you breathe per minute at the surface. Use the SAC Rate Calculator to find yours from logged dives.
Gas consumption increases with depth because the air is denser. At 20m you breathe 3x as much gas as at the surface.
• Fixed pressure allocation (50 BAR)
A simple planning input, not a universal recreational reserve or an emergency/minimum-gas calculation.
• Rule of thirds allocation
Allocates 1/3 outbound, 1/3 return, and 1/3 for contingencies. Appropriate use depends on the exit, team, cylinders, and training; compare it with minimum gas.
• Custom pressure allocation
Set a pressure allocation based on the trained plan. Choose whether it is the pressure left on the surface (usable gas must also cover the ascent) or the pressure at which the ascent begins, as in rock bottom / minimum gas planning, where the ascent is breathed from the reserve.
• Know your RMV rate
Track your SAC rate over multiple dives to get an accurate personal RMV
• Plan conservatively
Use a higher RMV than your average to account for currents, stress, and exertion
• Monitor during the dive
Check your SPG frequently and compare actual consumption to your plan
• Plan to surface with reserve intact
Plan to surface with the reserve intact; it is not planned bottom-time gas. In an emergency, it is contingency gas available to support the exit.