Free fitness tool

BMR Calculator

Estimate calories your body uses at rest.

Your BMR is the calories your body burns at complete rest. It's estimated with Mifflin-St Jeor and is not the same as your daily calorie target.

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What this calculator measures

Your Basal Metabolic Rate (BMR) is the minimum number of calories your body needs to sustain basic life functions at complete rest — breathing, circulation, temperature regulation, and organ function. BMR accounts for roughly 60–70% of total daily energy expenditure for most sedentary individuals.

How this calculator works

We use the Mifflin-St Jeor equation (1990), which is the most consistently validated BMR formula across large adult populations: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5 (men) or −161 (women). BMR is not the same as TDEE — it does not account for physical activity, and you should not use BMR as your daily calorie target.

How to use your result

Use BMR as a foundation for understanding your energy needs. To calculate how many calories you actually need day-to-day, multiply your BMR by your activity factor to get TDEE. If you want a number to eat at for gradual weight loss, use TDEE minus a 10–20% deficit, not BMR directly.

Important limitation

Calculator results are estimates. Pregnancy, eating disorders, medical conditions, injuries, or concerning symptoms require qualified professional guidance.

Methodology sources

Frequently asked questions

What's the difference between BMR and TDEE?

BMR is resting energy only. TDEE multiplies BMR by your activity level and is what you'd actually eat to maintain weight.

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