BMR Calculator
Free online BMR calculator. Discover your Basal Metabolic Rate and how many calories your body burns at rest.
Basal Metabolic Rate
1,673 cal/day
Mifflin–St Jeor
1,673 cal
Harris–Benedict
1,724 cal
TDEE by activity level
Method
How this calculator works
BMR estimates resting energy expenditure using body metrics. The Mifflin–St Jeor equation is the most widely recommended for its accuracy in clinical and fitness settings.
Mifflin–St Jeor:
Male: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Female: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
Harris–Benedict (revised):
Male: BMR = 88.362 + 13.397×weight + 4.799×height − 5.677×age
Female: BMR = 447.593 + 9.247×weight + 3.098×height − 4.330×age
TDEE = BMR × Activity Factor- Select your gender.
- Enter your age, weight (kg), and height (cm).
- The calculator computes BMR using both Mifflin–St Jeor and Harris–Benedict equations.
- TDEE is calculated for all five activity levels using BMR × multiplier.
- Choose the activity level that matches your lifestyle to find your maintenance calories.
Examples
Worked examples
Real numbers, end-to-end results.
Male · 25 yrs · 70 kg · 175 cm
BMR 1,673 cal · TDEE 2,592 (moderate)
Average young adult male.
Female · 30 yrs · 60 kg · 165 cm
BMR 1,311 cal · TDEE 1,806 (light)
Female with light exercise routine.
Male · 40 yrs · 85 kg · 180 cm
BMR 1,793 cal · TDEE 3,090 (active)
Active middle-aged male.
Use cases
When to use it
- Determine baseline calorie needs for weight loss or muscle gain.
- Set accurate calorie targets in a meal plan.
- Understand how aging and body composition affect metabolism.
- Compare two popular equations side by side.
Disclaimer: This calculator provides estimates for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for decisions affecting your health.
Sources: Formulas sourced from WHO BMI classifications, Mifflin-St Jeor equation (1990), Harris-Benedict equation, and NIH/CDC published guidelines. Not intended for clinical diagnosis.
FAQ
Frequently asked questions
What is Basal Metabolic Rate (BMR)?
Is BMR the same as TDEE?
How accurate are BMR calculators?
How can I increase my BMR?
Do I use my BMR to lose weight?
Methodology, assumptions & limitations
How we calculate: This calculator uses standard, peer-reviewed mathematical formulas implemented in TypeScript. All calculations run entirely in your browser — no data is sent to any server.
Assumptions: Unless stated otherwise, calculations assume constant rates over the specified period, no taxes or fees beyond those explicitly input, and standard compounding conventions for the formula type.
Limitations: Results are estimates for planning purposes. Real-world outcomes may differ due to variable rates, regulatory changes, taxes, fees, inflation, or other factors not modeled. This tool does not constitute medical advice or clinical diagnosis.
When NOT to use this: Do not rely solely on this calculator for medical decisions or diagnoses — always consult a qualified healthcare provider.
Feedback: Found an error or have a suggestion? Contact us — we review and correct reported issues within 48 hours.
Deep Dive Guide
What is BMR and How is It Calculated? (Mifflin–St Jeor vs Harris–Benedict)
Understand Basal Metabolic Rate — the calories you burn just by existing. Learn both major equations, what factors affect BMR, and how to use it for weight management.
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