Weight Loss & Nutrition
Connect calorie targets, macro planning, BMI context, and protein intake instead of checking each metric in isolation.
đĨ BMR Calculator
Calculate your Basal Metabolic Rate and daily calorie needs
đ Your Information
đ Your Results
Basal Metabolic Rate (BMR)
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calories/day
Sedentary (Little/No Exercise)
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Light Exercise (1-3 days/week)
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Moderate Exercise (3-5 days/week)
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Heavy Exercise (6-7 days/week)
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Athlete (2x per day)
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đ Your Information
âšī¸ The Mifflin-St Jeor equation is generally considered more accurate for modern populations.
đ Your Results
Basal Metabolic Rate (BMR)
--
calories/day
Sedentary (Little/No Exercise)
--
Light Exercise (1-3 days/week)
--
Moderate Exercise (3-5 days/week)
--
Heavy Exercise (6-7 days/week)
--
Athlete (2x per day)
--
đ Understanding Basal Metabolic Rate (BMR)
What is BMR?
Basal Metabolic Rate (BMR) is the number of calories your body needs to perform basic life-sustaining functions while at rest. This includes breathing, circulation, cell production, nutrient processing, and maintaining body temperature. BMR accounts for about 60-75% of your total daily energy expenditure.
Mifflin-St Jeor vs Harris-Benedict
Mifflin-St Jeor Equation (1990): Considered more accurate for modern populations. It was developed using data from diverse populations and is recommended by the Academy of Nutrition and Dietetics.
- Men: BMR = (10 Ã weight in kg) + (6.25 Ã height in cm) - (5 Ã age) + 5
- Women: BMR = (10 Ã weight in kg) + (6.25 Ã height in cm) - (5 Ã age) - 161
Harris-Benedict Equation (1919, revised 1984): One of the earliest BMR equations, still widely used but slightly less accurate than Mifflin-St Jeor.
- Men: BMR = 88.362 + (13.397 Ã weight in kg) + (4.799 Ã height in cm) - (5.677 Ã age)
- Women: BMR = 447.593 + (9.247 Ã weight in kg) + (3.098 Ã height in cm) - (4.330 Ã age)
Activity Level Multipliers (TDEE)
To calculate your Total Daily Energy Expenditure (TDEE), multiply your BMR by your activity level:
- Sedentary (1.2): Little or no exercise, desk job
- Lightly Active (1.375): Light exercise 1-3 days per week
- Moderately Active (1.55): Moderate exercise 3-5 days per week
- Very Active (1.725): Hard exercise 6-7 days per week
- Extra Active (1.9): Very hard exercise, physical job, or training twice per day
Factors Affecting BMR
- Age: BMR decreases by about 2% per decade after age 20
- Gender: Men typically have higher BMR due to greater muscle mass
- Body Composition: Muscle tissue burns more calories than fat tissue
- Genetics: Some people naturally have faster or slower metabolism
- Hormones: Thyroid hormones significantly affect metabolic rate
- Climate: Cold environments can increase BMR
- Pregnancy/Lactation: Increases energy requirements
- Illness/Fever: Can temporarily increase BMR
How to Use Your BMR
- Weight Loss: Eat 500-750 calories below your TDEE to lose 1-1.5 lbs per week
- Weight Maintenance: Eat at your TDEE level
- Weight Gain: Eat 300-500 calories above your TDEE to gain 0.5-1 lb per week
- Never eat below your BMR: This can slow metabolism and cause muscle loss
Tips to Boost Your Metabolism
- Build Muscle: Strength training increases muscle mass and BMR
- Stay Active: Regular exercise increases overall calorie burn
- Eat Protein: Protein has a higher thermic effect than carbs or fats
- Stay Hydrated: Dehydration can slow metabolism
- Get Enough Sleep: Poor sleep can negatively affect metabolism
- Don't Skip Meals: Eating regularly helps maintain metabolic rate
- Drink Green Tea: Contains compounds that may boost metabolism
- Manage Stress: Chronic stress can slow metabolism
Frequently Asked Questions
What's the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the calories you burn at complete rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by your activity level, representing the total calories you burn in a day including all activities.
Which formula is more accurate?
The Mifflin-St Jeor equation is generally considered more accurate for modern populations. It was developed in 1990 using more recent data and is recommended by the Academy of Nutrition and Dietetics. However, both formulas provide good estimates.
Can I eat below my BMR to lose weight faster?
No, eating below your BMR is not recommended. Your BMR represents the minimum calories needed for basic bodily functions. Eating below this level can slow your metabolism, cause muscle loss, fatigue, and nutritional deficiencies. Instead, eat between your BMR and TDEE for healthy weight loss.
Why does BMR decrease with age?
BMR decreases with age primarily due to loss of muscle mass and changes in hormonal levels. After age 20, BMR typically decreases by about 2% per decade. Regular strength training and staying active can help minimize this decline.
How accurate are BMR calculators?
BMR calculators provide estimates with about 10-15% accuracy for most people. They work best for individuals with average body composition. For more accurate measurements, consider indirect calorimetry testing at a lab or clinic. Factors like muscle mass, genetics, and health conditions can affect accuracy.
Does muscle really burn more calories than fat?
Yes! Muscle tissue burns about 6 calories per pound per day at rest, while fat burns only 2 calories per pound per day. This means that increasing muscle mass through strength training can boost your BMR and help you burn more calories even when you're not exercising.
How often should I recalculate my BMR?
Recalculate your BMR whenever you experience significant changes in weight (5+ pounds), age (yearly), or activity level. If you're actively losing or gaining weight, recalculate every 10-15 pounds to ensure your calorie targets remain appropriate.
đ§ Guided Journeys
Use a workflow instead of stopping at one result
These grouped paths are designed to help you continue with the most common follow-up calculations in this category.
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