BMR (Basal Metabolic Rate) is the number of calories your body needs to maintain basic life-sustaining functions at rest, such as breathing, circulation, and cell production.

What is the Mifflin-St Jeor equation?

The Mifflin-St Jeor equation is considered the most accurate BMR formula for most people. For males: 10×weight(kg) + 6.25×height(cm) − 5×age + 5. For females: 10×weight(kg) + 6.25×height(cm) − 5×age − 161.

How do I calculate daily calorie needs from BMR?

Multiply your BMR by an activity factor: Sedentary (×1.2), Light exercise (×1.375), Moderate exercise (×1.55), Active (×1.725), Very active (×1.9).

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BMR Calculator

Estimate your Basal Metabolic Rate (BMR) — the calories your body burns at rest — using multiple formulas.

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About BMR

Basal Metabolic Rate (BMR) is the number of calories your body needs to carry out basic life‑sustaining functions — breathing, circulation, nutrient processing, and cell production — while completely at rest.

How BMR is calculated

This calculator uses three established formulas:

Mifflin-St Jeor (1990): Considered the most accurate for most people. Male: 10W + 6.25H − 5A + 5. Female: 10W + 6.25H − 5A − 161.
Revised Harris-Benedict (1984): A widely used revision of the original 1919 formula.
Katch-McArdle (1996): Uses lean body mass, requiring body fat %. Formula: 370 + 21.6 × LBM.

From BMR to daily calories

BMR tells you calories burned at rest. To estimate total daily energy expenditure (TDEE), multiply BMR by an activity factor ranging from 1.2 (sedentary) to 1.9 (very active).

Tips for accurate inputs

Measure height without shoes and stand straight.
Use a recent weight measurement under similar conditions.
If you know your body fat %, enter it to enable the Katch-McArdle estimate.