BOLT score calculator.
A simple check of your CO₂ tolerance. Breathe normally, exhale gently, pinch your nose and time how long until you feel the first clear urge to breathe.
Free calculator
Estimates for general guidance, not medical advice. See the medical disclaimer and sources.
How it works
The formula.
Your result uses the same ten-step scale as Ritual Lab, moving up one rating for every 4.5 seconds of comfortable hold.
Questions
Frequently asked
What does BOLT stand for?
Body Oxygen Level Test.
Should I hold my breath as long as I can?
No. Stop at the first clear urge to breathe. It is a comfort test, not a maximum.
Is the BOLT score free in Ritual?
Yes. BOLT score is one of three calculators that are always free in Ritual.
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