BMR Calculator
The BMR Calculator estimates how many calories your body burns at complete rest. BMR is the foundation for calculating daily calorie needs and planning weight management strategies.
Educational estimate. Calculator results are for planning and information only, not financial, tax, medical, legal, or engineering advice. Verify important decisions with official sources or a qualified professional.
BMR Calculator
Calculate Basal Metabolic Rate
📐 Formula & Method
Mifflin-St Jeor (Men)
W = weight kg, H = height cm, A = age. Recommended by most dietitians.
Harris-Benedict (Men)
Older formula, still widely used.
📋 How to Use
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1
Select your gender.
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2
Enter age, weight, and height.
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3
Click "Calculate" to see BMR from two formulas.
What is BMR?
BMR is the energy (in calories) your body needs to maintain basic physiological functions at rest — breathing, circulation, cell production, and temperature regulation. BMR accounts for about 60–70% of total calorie expenditure.
🔬 Methodology & Accuracy
Formula: Uses the standard mathematical formula shown in the Formula & Method section above. All computations run client-side in your browser — no data is sent to our servers.
Data sources: Tax bands, contribution limits and regulatory rates are taken from official US (IRS, SSA) and UK (HMRC, gov.uk) publications for the current tax year, and updated when bands change.
Last reviewed: June 2026 · Accuracy: Results are precise to two decimal places using IEEE-754 double-precision arithmetic. Intended for educational and planning use only.
For informational purposes only. Results are estimates based on the inputs and formulas provided. For financial, tax, medical, or legal decisions, consult a qualified professional. Rates and regulations change — always verify current figures with official sources.