What is the Weir equation?

REE (kcal/day) = [3.941 × VO2 (L/min) + 1.106 × VCO2 (L/min)] × 1440.

How accurate is the Weir equation?

It is the gold standard indirect calorimetry calculation with less than 1% error when gas exchange is measured accurately.

Weir Equation VO2 VCO2 to REE

Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.

Weight (kg)

Height (cm)

⚕ Clinical Disclaimer: These calculators are for educational and reference purposes only. Always verify results with qualified clinical judgment and current clinical guidelines. Do not use as a sole basis for medical decisions.

How to use this calculator

1
Enter patient clinical data
Enter the patient's age, weight, lab values, vitals, or clinical findings into the Weir Equation VO2 VCO2 to REE input fields.
2
Select the clinical scoring system
Select or confirm the appropriate clinical scoring system or reference range for the patient population.
3
Calculate the clinical score
Press Calculate to compute the clinical score, risk estimate, or diagnostic result.
4
Interpret the result
Review the output against the provided reference ranges, risk categories, or guideline thresholds. Consult a qualified clinician before acting on results.

Formula

Result = f(patient inputs, clinical reference)

patient inputs: Age, weight, height, lab values, vitals, or clinical findings entered into the Weir REE Equation.
clinical reference: Reference range, scoring system, or population standard the result is compared against.
Result: Computed clinical score, risk estimate, or diagnostic value.

Clinical results are decision-support only and must be interpreted by a qualified clinician.

Glossary and Definitions

Clinical score: A numeric value derived from patient inputs that estimates risk, severity, or diagnostic likelihood for a given condition.
Reference range: The set of values considered normal for a healthy population, used to interpret a calculated result.
Sensitivity: The probability that a positive result correctly identifies a patient with the condition.
Specificity: The probability that a negative result correctly identifies a patient without the condition.
Weir equation: A key concept referenced by the Weir REE Equation: Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.
VO2: A key concept referenced by the Weir REE Equation: Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.
VCO2: A key concept referenced by the Weir REE Equation: Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.
REE: A key concept referenced by the Weir REE Equation: Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.
Energy expenditure: A key concept referenced by the Weir REE Equation: Calculate resting energy expenditure using the Weir equation from oxygen consumption and carbon dioxide production measured by indirect calorimetry.