BMR (Basal Metabolic Rate)

    BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to keep you alive — powering your organs, breathing, and cell function.

    Key facts

    • Usually the largest part of your daily calorie burn (60–70%).
    • Estimated from gender, age, weight, and height.
    • The base that activity multipliers are applied to for TDEE.
    • Larger bodies and more muscle raise BMR.

    BMR is the energy cost of simply existing. Even if you stayed in bed all day, your body would burn this many calories running your heart, brain, liver, and other organs. For most people it accounts for the majority of total daily calorie expenditure.

    It is most commonly estimated with the Mifflin-St Jeor equation, which uses your gender, age, weight, and height. Your TDEE is then calculated by multiplying BMR by an activity factor. Because muscle is more metabolically active than fat, building muscle nudges BMR up over time.

    Try the calculator

    TDEE Calculator

    Calculate your Total Daily Energy Expenditure

    TDEE Calculator

    Frequently asked questions

    What is the difference between BMR and TDEE?

    BMR is what you burn at rest. TDEE is BMR plus the calories from activity, exercise, and digestion — your full daily burn.

    Can you increase your BMR?

    Somewhat. Building muscle raises it modestly because muscle tissue burns more energy at rest than fat. Crash diets can temporarily lower it.

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