How to use the respiratory quotient calculator
Find the respiratory quotient from CO₂ and O₂ exchange. Enter co₂ produced, o₂ consumed in the fields above; the respiratory quotient, likely fuel are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- co2 — CO₂ produced (mL/min)
- o2 — O₂ consumed (mL/min)
Worked example
With co₂ produced = 200 mL/min, o₂ consumed = 250 mL/min, the calculator gives respiratory quotient ≈ 0.8; likely fuel ≈ Mostly fat.
Frequently asked questions
What is the formula for the respiratory quotient calculation?
Respiratory quotient = co2 / o2. Likely fuel = [Respiratory quotient]>0.95?"Mostly carbohydrate":([Respiratory quotient]>0.8?"Mixed":"Mostly fat"). Here co2 is co₂ produced (mL/min), o2 is o₂ consumed (mL/min).
What inputs do I need for the respiratory quotient calculator?
You need co₂ produced in mL/min, o₂ consumed in mL/min. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.