CO2 table for freediving
The CO2 table generator, opened at the load a certified freediver trains on dry land: a 120-second maximum on Classic. Sixty-second holds, seven rounds, and a rest that falls from 40 seconds to 10.
This is a land session that supports diving. It does not replace time in the water, and it is not a substitute for a buddy.
Opens with the freediving preset already set
- Maximum breath hold: 120 seconds
- Difficulty: Classic (hold at 50% of your max)
- Hold: 60 seconds, every round
- Session: 7 rounds, 9 minutes 40 seconds
Set to a dry two-minute maximum. If yours is different, move the slider and press generate — the rest of the table rescales from it.
Enter your best breath hold time. If you're unsure, try our breath hold timer first.
Your CO₂ training table
| Round | Breathe (Rest) | Hold | Round Total |
|---|---|---|---|
| 1 | 0:40 | 1:00 | 1:40 |
| 2 | 0:34 | 1:00 | 1:34 |
| 3 | 0:28 | 1:00 | 1:28 |
| 4 | 0:22 | 1:00 | 1:22 |
| 5 | 0:16 | 1:00 | 1:16 |
| 6 | 0:10 | 1:00 | 1:10 |
| 7 | 0:10 | 1:00 | 1:10 |
Hold time: 1:00 (50% of your max) — stays constant each round.
Rest time: Starts at 0:40 and drops 6 seconds per round (minimum 10s) while the hold stays steady.
Run this table
Use the browser timer only while seated or lying down on dry land. Stop whenever you need to breathe. Never use it for breath holding in water.
Ready
Review every interval before starting
Train with this table in the BreathHold app
Get guided audio cues, haptic feedback, and automatic progress tracking.
Use your dry maximum, not your wet one
A static in the pool after a proper warm-up, with your face in the water and the dive reflex working for you, is longer than anything you will do sitting on a sofa. Feed that number into a dry table and every round asks for a hold you cannot repeat on land.
Take a dry maximum in the same conditions you will run the table in: seated, no warm-up dives, no cold water on the face. For most divers who hold three minutes wet, the dry number lands nearer two. That is why the preset is 120 and not 180.
A 60-second hold is a working dive, not a test
Classic sets the hold at half your input, so 120 seconds gives 60. A minute is roughly a comfortable recreational descent and return, and that is the point: you are practising the length you actually use, seven times, with less and less recovery.
The first contractions usually arrive somewhere in the second half of a hold that length. By round five or six they will arrive earlier, because the rest has shrunk. Staying still and unbothered when they come is the skill that transfers to a line.
When Hard is the wrong answer
Hard sets the hold at 60 percent of your maximum and takes the rest away twice as fast. At a 120-second input that is a 72-second hold starting from 36 seconds of rest, and most divers cannot finish it without breaking form somewhere around round five.
Raise the input before you raise the difficulty. A Classic table at 140 seconds is a better session than a Hard table at 120, because you hold longer and still recover enough to stay relaxed. Move to Hard when the Classic table at your real dry maximum feels routine.
What divers get wrong on a dry table
- Packing or purging before a round. Neither belongs in a table. Both change the measurement and one of them is dangerous. Read the safety guide.
- Running it the day before a deep session. A full CO2 table leaves you flat. Put two days between the table and anything you care about.
- Treating the last round as a max attempt. The hold never changes. If you push round seven longer than the others you have run a different session.
- Doing it in the water alone. A table is not a reason to be in a pool without a trained buddy watching the recovery.
What the generator produces across the freediving range
Run 2026-09-04: generateCO2Table from lib/training-tables.ts on Classic, at maximum holds from 90 to 240 seconds in 10-second steps — 16 inputs, seven rounds each; six of them shown.
| Max hold | Hold | First rest | Rest drop | Shortest rest | Floor at round | Session |
|---|---|---|---|---|---|---|
| 90s | 45s | 30s | 5s | 10s | 5 | 7:15 |
| 120s | 60s | 40s | 6s | 10s | 6 | 9:40 |
| 150s | 75s | 50s | 8s | 10s | 6 | 11:55 |
| 180s | 90s | 59s | 9s | 10s | 7 | 14:19 |
| 210s | 105s | 69s | 10s | 10s | 7 | 16:49 |
| 240s | 120s | 79s | 12s | 10s | 7 | 19:04 |
All 16 inputs reach the 10-second rest floor, unlike the beginner range, where one input never does. Sessions run from 7:15 to 19:04. The preset is 9:40, which fits inside a warm-up.
Where the floor lands is the useful number, and it does not move smoothly: rounding the per-round drop to whole seconds makes it jump between round five and round seven across the range. At 90 seconds the last three rounds are identical. From about 110 seconds up the floor arrives on the final round only, so the table ramps the whole way down instead of flattening — that is the version worth running.
The far end is where it stops being sensible rather than where it breaks. At a 240-second input the generator hands you a two-minute hold with 10 seconds of breathing between the last rounds. The maths is fine. The session is a competition-grade demand, and the tool will not warn you.
Questions
- What CO2 table should a freediver use?
- Classic difficulty at your dry maximum. This page opens at a 120-second maximum, which gives 60-second holds and rests from 40 down to 10 seconds across seven rounds, 9 minutes 40 seconds in total.
- Should I enter my pool static or my dry maximum?
- Your dry maximum, measured seated with no warm-up dives and no facial immersion. A wet static benefits from the dive reflex and is commonly a minute longer, so using it produces a dry table you cannot complete.
- How does a CO2 table help freediving?
- It repeats a hold at a fixed length with less recovery each round, so the urge to breathe arrives earlier while the demand stays the same. It trains your response to that urge. It does not increase lung capacity, and no table guarantees a depth or a time.
- When should I switch from Classic to Hard?
- When a Classic table at your true dry maximum feels routine through all seven rounds. Before that, raise the input rather than the difficulty: a Classic table at 140 seconds is a longer hold with more usable recovery than a Hard table at 120.
- How often can I run this table?
- Twice a week at most, and not the day before a deep or long session. Leave two days between a full CO2 table and any diving you care about.
- Can I run this table in the pool?
- Only with a trained buddy watching every hold and every recovery, and only if you are certified. Alone, it is a dry-land session and nothing else.
Where to go next
- CO2 table generator — the full tool, if you want Hard or a maximum outside the freediving range
- CO2 table for beginners — the Easy preset at a 60-second maximum, for someone starting from nothing
- Static apnea training tables — a 90-second base you can edit round by round before running it
- What is static apnea — the discipline these dry sessions feed, and the certification times that go with it