A full deco planner in your pocket, and a free toolkit around it.

Bühlmann ZH-L16C with gradient factors: 16 tissue compartments, helium and nitrogen tracked separately at their published half-times, tissues recomputed in 1-second steps through descent, bottom, and ascent. The engine is written in C++ from the published papers. The full implementation is documented in the guide, including the non-obvious design choices and why we made them. Read how the engine works.

We ran the same 26 dives through both planners at the same ascent rates and published everything: inputs, outputs, and a written note on every difference. The depth where decompression begins agrees within about one deco step on nearly every scenario, gas switches land at the same depths, and the oxygen clocks agree within a few percent. Browse the side-by-side comparison.

It runs the same model family with the same gradient factor controls, so schedules line up when the settings match, but any two implementations differ in small ways. Plan in Dive Kit, dive your computer. If you find a disagreement you can't explain, email me the plan link and I'll look into it: [email protected].

Fair question. You are paying for a mobile-first planner with CCR setpoint schedules, bailout plans, automatic contingencies, oxygen air breaks, and shareable plans, maintained full time. If a free desktop tool covers your needs, use it. The other eleven tools in Dive Kit are free regardless.

Yes. The monthly plan starts with a free trial; cancel before it converts and you pay nothing. There is also a $24.99 lifetime purchase with no subscription at all. Prices show in your store's currency.

Shared plans stay readable. Anyone can open a shared plan in the app or in a browser and read the full schedule without a subscription; only creating and editing plans is paid. How plan sharing works.

I can't promise the future, but I can show the past: the roadmap lists everything shipped, dated, and the engine changelog goes down to individual fixes. The other half of the answer: decompression math doesn't expire. Bühlmann's papers are decades old, a gas law won't deprecate, and an app that needed constant updates to stay useful would have been built wrong. I'll keep shipping what divers need and folding in new research as it's published. If updates one day slow to maintenance and research, that means the toolkit is finished, not abandoned — and that I'm busy building the next thing on the roadmap, like the cave planner.

No. It has no depth sensor and tracks nothing underwater. Dive Kit is a planning tool you use on the surface. Always dive a real dive computer.

Everything runs on the phone: no account, no connection, no tracking. It is built for boats without signal. The only things that need internet are downloading the app and opening shared plan links in a browser.

No dive log yet, no VPM (it runs dissolved-gas Bühlmann, so a VPM-only planner will not produce a matching schedule), and no dive computer sync. The model also assumes things about you that may not be true on the day. Read the assumptions before you trust any plan.

Setpoint schedules with mid-ascent switches, diluent switches (dilout) with flush gas accounting, stay-on-loop deco, full bailout schedules, and bailout-at-depth views. The published cross-reference includes CCR scenarios you can open and rerun yourself. How CCR planning works.

Eleven tools: free forever, no ads, no account. The Deco Planner: free trial, then $4.99/month, or $24.99 once. Download Dive Kit and the free tools are yours either way.