Dive planner
Plan any recreational dive in seconds. Enter a depth, a time and your gas, and get your no-decompression limit, nitrox limits and air consumption — all in metres, all computed from the physics. Free, and no sign-up needed.
This plan runs the cylinder below your 50 bar reserve. Shorten the dive, take a bigger cylinder, or plan a shallower profile.
These are conservative estimates from the numbers you enter, assuming a square profile and modelling nitrogen and oxygen only. They say nothing about the conditions, cold, workload, your fitness, or your actual ascent. Always dive with a computer, analyse your own cylinder, and plan every dive with your dive centre and buddy. Never plan a decompression dive with this tool.
The full planner adds repetitive dives with surface intervals (your second dive’s no-stop time, carried through the model), a best-mix optimiser, your saved breathing rate, and saved plans. Free with a diver account.
What the planner works out
No-decompression limit (NDL). The longest you can stay at a depth on a given mix and still ascend directly to the surface. We compute it with the Bühlmann ZH-L16 tissue model and a conservative margin, so it lands at or inside the limits on your training tables.
Nitrox MOD and EAD.The maximum operating depth keeps you under the oxygen partial-pressure limit; the equivalent air depth tells you how “deep” a nitrox dive feels for narcosis and nitrogen loading. See the full dive tables for every mix at a glance.
Gas planning. How much of your cylinder the dive actually breathes — bottom time plus ascent and a safety stop — with a turn-around pressure for out-and-back dives and a reserve kept back.
Frequently asked questions
▸What does this dive planner calculate?
For a depth, time and breathing gas it gives you the no-decompression limit (how long you can stay before a decompression obligation), the nitrox MOD and equivalent air depth, the oxygen partial pressure at depth, and how much gas the dive will use against your cylinder — including ascent and a safety stop.
▸How are the no-decompression limits worked out?
They're computed with Albert Bühlmann's ZH-L16 decompression model and a conservative gradient factor — not copied from any agency's table. The result sits at or inside the recreational limits your training tables show, so the planner is never more permissive than the tables you already trust.
▸What breathing rate should I use?
Your surface air consumption (SAC or RMV) in litres per minute. If you don't know yours, 20 L/min is a sensible, slightly conservative default for a relaxed adult. Signed-in divers can save their real rate so it's remembered.
▸Can I use this instead of a dive computer?
No. It's a planning aid that assumes a square profile and models nitrogen and oxygen only. Always dive with a computer, analyse your own cylinder, and plan every dive with your dive centre and buddy.
Looking for the reference numbers instead of a calculator? The dive tables and the rest of our useful information for divers are free and open to everyone.