Quick Summary
GreatHealthGear RatingThe Carbon Free Breathing Trainer is a functional CO₂ tolerance training tool for users who want structured breath-hold and CO₂ rebreathing exercises beyond basic slow breathing. The CO₂ tolerance training concept has physiological merit; the specific device evidence base is limited. Suitable as one component of a breathwork practice rather than a standalone solution.
Ideal for
- Users who want structured CO₂ tolerance training with a dedicated tool
- Athletes interested in improving breathing economy and dyspnoea tolerance
- Users exploring Buteyko or CO₂ tolerance methods who want more structure than the Relaxator
- Those who have plateaued on basic slow breathing and want a progression
Not ideal for
- Users who want respiratory muscle strength training (choose POWERbreathe or Airofit)
- HRV biofeedback users (choose HeartMath Inner Balance)
- Beginners who have not established basic nasal breathing habits first
- Users looking for a device with comprehensive app guidance and progress metrics
Available at
Carbon Free Official
Check current price
Pros & Cons
- + Structured CO₂ tolerance training tool beyond basic breath pacing
- + Supports breath-hold and CO₂ rebreathing protocols
- + Portable and simple to use
- + Addresses a specific training modality not covered by IMT devices
- - Device-specific published evidence is limited
- - No app, no metrics, no guided feedback
- - CO₂ tolerance training carries safety considerations — breath-holding requires appropriate practice context
- - Not suitable as the primary breathwork tool for most users
Respiratory contraindication note: Consult a healthcare professional before beginning respiratory muscle training or breath-hold training if you have asthma, COPD, cardiovascular disease, or other respiratory conditions. Do not practise breath-holds alone, in water, or after hyperventilation. Do not use respiratory trainers during acute illness.
Design & Build Quality
The Carbon Free Breathing Trainer is a compact device designed for breathing exercise protocols involving CO₂ rebreathing or controlled breath-hold training. Build quality is functional — appropriate for a dedicated breathing tool at this price range. Portability is good; the device is small enough for a training bag or travel kit.
Setup & Ease of Use
Setup is straightforward — the device uses simple mechanical protocols rather than app-guided sessions. Understanding the appropriate training protocol requires self-directed research or following the guidance provided by Carbon Free Breathing. The learning curve is moderate: users need to understand CO₂ tolerance concepts to use the device effectively.
Training Performance
CO₂ tolerance training addresses a real physiological phenomenon — over-breathing relative to metabolic demand is common, and building CO₂ tolerance can improve breathing efficiency. The specific Carbon Free Breathing Trainer device has limited published device-specific evidence, but the underlying training principles (CO₂ rebreathing, breath-hold progression) are consistent with Buteyko method literature and sports science work on breathing economy.
For users who have already established nasal breathing habits and want to progress CO₂ tolerance specifically, the device provides structured training beyond what the Relaxator offers.
Features & Programmes
No app. Protocol guidance from Carbon Free Breathing materials. The device is single-purpose — CO₂ tolerance training protocols.
Battery Life
No battery. Fully mechanical device.
App & Software Experience
No app. Standalone device.
Data Privacy
No data collected. Standalone mechanical device.
Value for Money
Value depends on how specific your CO₂ tolerance training goal is. For users who have researched CO₂ tolerance training and want a dedicated tool, the price is reasonable. For users who are not sure whether CO₂ tolerance training is their primary goal, the Relaxator at $30 is the lower-risk starting point.
Final Verdict
The Carbon Free Breathing Trainer is a useful tool for users who specifically want structured CO₂ tolerance training as part of an established breathwork practice. It is not the right first breathwork device, and it does not replace respiratory muscle training or HRV biofeedback.
As part of a comprehensive breathing practice alongside tools like the POWERbreathe Medic Plus (for IMT) or HeartMath Inner Balance (for HRV biofeedback), it fills a specific training niche that the other devices do not cover.
Who Should Buy?
Buy the Carbon Free Breathing Trainer if: You have an established breathwork practice, understand CO₂ tolerance training, and want a dedicated tool for breath-hold and CO₂ rebreathing protocols.
Skip it if: You are new to breathwork (start with the Relaxator or POWERbreathe), want app guidance and metrics, or want respiratory muscle strength training.
Final Verdict
The Carbon Free Breathing Trainer is a functional CO₂ tolerance training tool for users who want structured breath-hold and CO₂ rebreathing exercises beyond basic slow breathing. The CO₂ tolerance training concept has physiological merit; the specific device evidence base is limited. Suitable as one component of a breathwork practice rather than a standalone solution.
Check current price
at Carbon Free Official
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Who Should Buy the Carbon Free Breathing Trainer Review?
Buy it if you...
- Users who want structured CO₂ tolerance training with a dedicated tool
- Athletes interested in improving breathing economy and dyspnoea tolerance
- Users exploring Buteyko or CO₂ tolerance methods who want more structure than the Relaxator
- Those who have plateaued on basic slow breathing and want a progression
Skip it if you...
- Users who want respiratory muscle strength training (choose POWERbreathe or Airofit)
- HRV biofeedback users (choose HeartMath Inner Balance)
- Beginners who have not established basic nasal breathing habits first
- Users looking for a device with comprehensive app guidance and progress metrics
Comparison With Alternatives
Carbon Free Breathing Trainer vs Relaxator
The Relaxator ($30) is a breath-pacing tool using exhalation resistance to slow breathing. The Carbon Free Breathing Trainer adds structured CO₂ rebreathing protocols for more specific CO₂ tolerance development. They address adjacent aspects of CO₂ tolerance training — the Relaxator is the simpler and cheaper starting point; the Carbon Free Trainer is a progression for users who want more specific CO₂ protocol work.
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