Plan the decompression
Depth, time, gases and gradient factors in; stops, runtime, CNS and a gas budget out — recalculated as you type, with contingencies for the dive that does not go to plan.
A planner and simulator on a real decompression model, a logbook your dive centre stamps, and the desk your centre runs its day from: trips and the boat manifest, kit out and back, courses and sign-offs.
Runtime
0:37h:mm
Max depth
30m
Deco
7min
Ascent
0:12h:mm
Stops
| 9 m | 1 min | 0:30 |
| 6 m | 2 min | 0:32 |
| 3 m | 4 min | 0:37 |
Tissues
What’s inside
One model, used the same way everywhere: to plan the dive, to fly it, and to check the one you came back from.
Depth, time, gases and gradient factors in; stops, runtime, CNS and a gas budget out — recalculated as you type, with contingencies for the dive that does not go to plan.
Run the dive live or up to 60× faster on auto depth or by hand on buoyancy. Inject a free-flow or a runaway loop and practise the bad day before it happens.
Close a trip and every diver on it finds the dive waiting in their logbook, replayed through the model. Confirm it and the centre’s own stamp lands on the page.
Today at a glance: who is diving, which kit is out or overdue, what waits for a signature. Trips with groups and check-in, the fleet, the fill station, the manifest on paper.
Lessons, graded quizzes, skills an instructor signs off, drills flown in the simulator and plans rehearsed before the boat. Students see what is next; staff see who needs them.
Import Subsurface, UDDF, Garmin FIT, Suunto or CSV logs and get findings pinned to the moment they happened: ceiling violations, fast ascents, surfacing GF.
A closed loop stays on the loop; bailout is a decision you make, not one the planner makes for you. A semi-closed loop runs leaner than its supply gas.
Rock bottom and turn pressures, partial-pressure blending, best mix for a depth and narcosis budget, and gas density flagged against the 5.2 g/L guidance.
The model is pure and dependency-free, so the same planner runs in an offline Android build — on a boat, with no bars, forever.
Analyse a real dive
Load the log from your dive computer and DiveSim replays it through the same Bühlmann model the planner uses — ceiling, supersaturation and ppO₂ over time, with each finding pinned to the moment it happened.
The file is read on your device and stays there unless you save the dive to your logbook.
Premantura cave entrance
UDDF · Shearwater Petrel 3 · 30 m · 32 min
Up to 2.7 m shallower than this model allowed, from 31:40.
From 24 m to the surface, peaking around 21 m. The usual limit there is 10 m/min.
From 200 to 18 bar on a 12 L cylinder. Use it as your planning SAC.
A model you can audit
Coefficients transcribed from two independent published sources that agree digit for digit. Schreiner integration for travel segments. Alveolar water vapour subtracted wherever inert gas is taken up.
These no-stop limits come from the model by bisection. Every one is asserted in the test suite, so a change to the engine that moves them fails the build.
Free, runs in your browser, and there is an offline Android build for the boat.