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Basal Metabolic Rate Converter

Convert basal metabolic rate between units instantly. Includes conversion tables, common equivalents, and calculation formulas.

Reviewed by Manoj Kumar, Mathematics Educator

Reviewed by Manoj Kumar, Mathematics Educator

Formula

BMR (Male) = (10 x weight kg) + (6.25 x height cm) - (5 x age) + 5

The Mifflin-St Jeor equation calculates BMR using weight in kilograms, height in centimeters, and age in years. For females, the constant is -161 instead of +5. TDEE = BMR x Activity Factor, where sedentary = 1.2, light = 1.375, moderate = 1.55, active = 1.725, very active = 1.9. The Harris-Benedict equation uses different coefficients, and the Katch-McArdle formula uses lean body mass: BMR = 370 + (21.6 x lean mass kg).

Worked Examples

Example 1: BMR for a 30-Year-Old Male

Problem:Calculate BMR for a 30-year-old male, 70 kg, 170 cm, with moderate activity level.

Solution:Mifflin-St Jeor: BMR = (10 x 70) + (6.25 x 170) - (5 x 30) + 5\nBMR = 700 + 1062.5 - 150 + 5 = 1,618 calories/day\nTDEE = 1,618 x 1.55 (moderate activity) = 2,507 calories/day\nBMR per hour: 1,618 / 24 = 67.4 calories/hour\nWeight loss target: 2,507 - 500 = 2,007 calories/day\nWeight gain target: 2,507 + 500 = 3,007 calories/day

Result:BMR: 1,618 cal/day | TDEE: 2,507 cal/day | Weight loss: 2,007 cal/day

Example 2: BMR for a 45-Year-Old Female

Problem:Calculate BMR for a 45-year-old female, 60 kg, 165 cm, with light activity.

Solution:Mifflin-St Jeor: BMR = (10 x 60) + (6.25 x 165) - (5 x 45) - 161\nBMR = 600 + 1031.25 - 225 - 161 = 1,245 calories/day\nTDEE = 1,245 x 1.375 (light activity) = 1,712 calories/day\nWeight loss target: 1,712 - 500 = 1,212 calories/day\nThis is very close to BMR, so a smaller deficit of 300 cal might be safer.

Result:BMR: 1,245 cal/day | TDEE: 1,712 cal/day | Safe deficit: ~1,412 cal/day

Frequently Asked Questions

What is Basal Metabolic Rate and how does it differ from TDEE?

Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to maintain basic life-sustaining functions such as breathing, circulation, cell production, nutrient processing, and temperature regulation. BMR accounts for approximately 60-75% of total daily energy expenditure. Total Daily Energy Expenditure (TDEE) includes BMR plus calories burned through physical activity (15-30% of total), the thermic effect of food (approximately 10% of calories consumed for digestion), and non-exercise activity thermogenesis (NEAT) like fidgeting and walking. Understanding the difference between BMR and TDEE is crucial for setting accurate calorie targets for weight management.

What factors affect Basal Metabolic Rate?

Several factors significantly influence BMR. Body composition is the primary determinant: muscle tissue burns approximately 6 calories per pound per day at rest compared to 2 calories per pound for fat tissue, which is why muscular individuals have higher BMRs. Age causes BMR to decline by roughly 1-2% per decade after age 20, primarily due to muscle loss. Men typically have 5-10% higher BMR than women of the same weight due to greater muscle mass. Genetics account for approximately 40% of BMR variation between individuals. Hormones, particularly thyroid hormones, significantly regulate metabolic rate. Environmental temperature, caffeine intake, pregnancy, illness, and certain medications can also temporarily alter BMR.

References

Reviewed by Manoj Kumar, Mathematics Educator · Editorial policy