BMR Calculator
Calculate your Basal Metabolic Rate and daily calorie needs
Calculate Your BMR
Your Results
🔥 Quick Answer
Your BMR is 1,649 calories/day - this is what your body burns at complete rest. With your moderately active lifestyle, your TDEE is 2,556 calories/day. To lose weight, aim for 2,056 calories. To gain weight, aim for 3,056 calories.
Dr. Snezana Lawrence
Mathematical Historian
15+ years experience
PhD from Yale University. Published mathematical historian ensuring precision in all calculations.
Education
PhD in Mathematical History - Yale University
📑 Table of Contents
🤔 What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to perform essential life-sustaining functions while at complete rest. These functions include:
Basic Functions
- • Breathing and circulation
- • Cell production and repair
- • Brain function
- • Body temperature regulation
Key Facts
- • Accounts for 60-75% of daily calories
- • Measured in a resting state
- • Varies by age, gender, and body composition
- • Foundation for calorie planning
📐 BMR Formulas Explained
Mifflin-St Jeor Equation (Recommended)
Most accurate for most people:
Men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) - 161
Harris-Benedict Equation (Revised)
Classic formula, still widely used:
Men: BMR = (13.397 × weight) + (4.799 × height) - (5.677 × age) + 88.362
Women: BMR = (9.247 × weight) + (3.098 × height) - (4.330 × age) + 447.593
🏃 Activity Level Multipliers
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Little or no exercise, desk job |
| Lightly Active | 1.375 | Light exercise 1-3 days/week |
| Moderately Active | 1.55 | Moderate exercise 3-5 days/week |
| Very Active | 1.725 | Hard exercise 6-7 days/week |
| Extra Active | 1.9 | Very hard exercise, physical job |
📊 Factors Affecting BMR
Muscle Mass
More muscle = higher BMR. Muscle burns more calories than fat.
Age
BMR decreases ~2% per decade after age 20.
Gender
Men typically have higher BMR due to more muscle mass.
Genetics
Inherited metabolic rate can vary significantly.
💡 Tips for Managing Calories
- Weight Loss: Create a 500 calorie/day deficit to lose ~1 lb/week (healthy pace)
- Weight Gain: Create a 500 calorie/day surplus to gain ~1 lb/week
- Don't Go Too Low: Never eat below your BMR - it can slow metabolism
- Build Muscle: Strength training increases BMR over time
- Track Accurately: Use a food scale and track everything you eat
❓ Frequently Asked Questions
What is BMR?
BMR (Basal Metabolic Rate) is the number of calories your body needs to perform basic life-sustaining functions while at complete rest.
What's the difference between BMR and TDEE?
BMR is calories burned at rest. TDEE (Total Daily Energy Expenditure) includes all calories burned including physical activity. TDEE = BMR × Activity Factor.
How accurate is the BMR calculation?
BMR formulas are estimates with about 10% error margin. The Mifflin-St Jeor equation is considered most accurate for most people.
Can I increase my BMR?
Yes! Building muscle through strength training is the most effective way to increase BMR. Getting adequate sleep and staying hydrated also helps optimize metabolism.
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Dr. Snezana Lawrence
Mathematical Historian | PhD from Yale
Dr. Lawrence is a published mathematical historian with a PhD from Yale University. She ensures mathematical precision and accuracy in all our calculations, conversions, and academic score calculators. Her expertise spans computational mathematics and educational assessment.
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