BMR Calculator

Last updated: July 4, 2026
Reviewed by Dr. Alana Reyes, MD

About this Calculator

Your Basal Metabolic Rate (BMR) represents the absolute minimum number of calories your body needs to survive while at complete rest.

Formula & Calculations

Mathematical Formula

Mifflin-St Jeor vs. Revised Harris-Benedict (1984)

Evaluates rest energy needs in a neutral environment.

How to Calculate Step-by-Step

1

Input profile

Age, gender, weight, and height.

2

Select equation

Choose MSJ or Harris-Benedict.

3

Calculate BMR

Outputs resting energy needs.

How to Use & Best Practices

Input details and choose which equation formula to run.

Frequently Asked Questions

What is the difference between BMR and RMR?

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BMR requires strict waking conditions and fasting; RMR is measured without fasting.

Dr. Alana Reyes, MD, MPH Clinical Reviewer

Dr. Reyes is a board-certified endocrinologist specializing in metabolic health and metabolic disorders.

Want to learn more about this calculator?

Ask our AI assistant for explanations, formulas, or usage advice.

Calculate BMR

Gender
Your BMR 1630 kcal/day
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