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BMR Calculator

Determine your Basal Metabolic Rate—the exact number of calories your body burns at complete rest just to stay alive.

Enter Your Parameters

Gender

Age (Years)

Height (cm)

Weight (kg)

Physical Activity Level

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Understanding Your Result

The calculation generated by this tool provides an evidence-based assessment derived from established physiological and clinical equations. Use this measurement as an educational indicator alongside broader lifestyle variables, including overall dietary quality, resistance training, cardiovascular endurance, and routine medical checkups.

Mathematical Formula & Scientific Methodology

The Mifflin-St Jeor equation calculates BMR based on gender, weight, height, and age. For Men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5. For Women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161.

\text{Men: } BMR = 10W + 6.25H - 5A + 5 \quad | \quad \text{Women: } BMR = 10W + 6.25H - 5A - 161

Step-by-Step Example Calculation

For a 30-year-old male weighing 80 kg and 180 cm tall: BMR = (10 × 80) + (6.25 × 180) - (5 × 30) + 5 = 800 + 1125 - 150 + 5 = 1,780 kcal/day.

Clinical Limitations & Nuances

BMR formulas are mathematical estimations derived from population averages. They do not account for variations in thyroid hormone levels, genetics, ambient temperature, or individual lean muscle mass percentage.

Frequently Asked Questions

What is the difference between BMR and RMR?

BMR (Basal Metabolic Rate) is measured under strict laboratory conditions immediately upon waking after 8 hours of sleep and 12 hours of fasting. RMR (Resting Metabolic Rate) is slightly less restrictive and typically measures 5-10% higher than BMR.

Should I ever eat below my BMR?

Eating consistently below your BMR for extended periods is generally not recommended without physician supervision, as it may lead to nutrient deficiencies, hormonal imbalances, and loss of lean muscle mass.

How can I increase my BMR?

Increasing lean muscle tissue through progressive resistance training is the most effective long-term method to raise your resting metabolic rate, as muscle tissue burns more calories at rest than fat tissue.

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