Apnea Trainer
free
Dry training for breath-holding: CO2 and O2 tables calculated from your own best time — seven grades, on land only.
Before you begin
This app does not replace apnea training instruction. It contains exclusively dry exercises for training on land — no timer ever starts a breath-hold in water.
- Apnea training in water never takes place alone. A blackout gives no warning and happens silently. Without a trained partner within reach it is fatal.
- Practise sitting or lying down — not standing, not in water, not in a car.
- Hyperventilation before a breath-hold is dangerous: it pushes back the urge to breathe, not the loss of consciousness. The app deliberately offers no such protocol and explains why in the knowledge section.
- With cardiovascular disease, epilepsy, lung conditions or during pregnancy, seek medical advice first.
No sign-up. No ads. No tracking. If you like, you can support the project voluntarily.
What is it?
Holding your breath longer can largely be trained on land. The apnea trainer recalculates CO2 and O2 tables against your own best time and walks you through the session — block by block, with a timer and announcements.
Seven grades lead from the first attempt to competition level. Moving up does not depend on times alone: every grade has a test, and there is no way past it.
How it works
- Do the maximum test once — it gives the best time everything else is measured against.
- Choose a table: CO2 shortens the pauses, O2 lengthens the holds.
- The app leads you through the session block by block, with timer and announcements.
- The next grade comes with a test — pass it and you move on.
Alongside that: an exercise library of 15 exercises and a knowledge section on the diving reflex, blackout and samba, the buddy system, equalising and equipment.
Who is it for?
For freedivers who want to keep working between water sessions, and for anyone starting out with dry training.
Not for learning to freedive in the first place: that happens in a course, with an instructor, in the water.
What you get
- Gradesseven, from beginner to competition level
- TablesCO2 and O2, calculated from your own best time
- Exercises15 in four categories — mobility, breathing, tolerance, technique
- Knowledge section10 topics, plus one test question per grade
- Water sessionsnone — training on land only
Privacy and technology
Runs entirely in your browser. Your progress stays on your device and is sent nowhere — no account, no sign-up, no ads, no tracking. The share menu puts the app on your home screen; after that it works without an internet connection as well.
Because nothing sits on a server, nothing can be fetched back from one: clear your browser data and your progress is gone. That is why More offers Create backup — a file you can keep and load again, on another device too.
Common questions
Can I learn to freedive with this?
No. The app contains dry exercises only and never starts a timer for a hold in water. Freediving is learned in a course — that is not a formality but the difference between a sport and a mortal danger.
Why does the app not offer hyperventilation?
Because it pushes back the urge to breathe, not the loss of consciousness. You feel comfortable for longer and black out just as early — only without warning. The knowledge section explains this at length.
Where do my times come from?
From the maximum test. Every table is calculated as a share of that best time, not as a fixed number of seconds. A new test therefore shifts the whole session.
Can I take my progress to another device?
Yes. Create backup writes a file you can load on the other device. Without that file your progress is gone once the browser data is cleared — there is no server.
Open the trainingSomething missing? Something wrong?
If you notice anything — a mistake, a suggestion, or a tool that is not here yet — write to me. I am glad about every message, though I cannot always reply straight away.
Support
This app is free and stays free. If it has been useful to you, a voluntary contribution helps build the next one.
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