About the Calorie & BMR Calculator
What is this?
Your Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest just to keep you alive — breathing, circulating blood, maintaining body temperature, and powering your organs. It represents roughly 60–75% of the energy you expend each day. Total Daily Energy Expenditure (TDEE) builds on BMR by adding the calories you burn through daily activity and exercise, giving you a realistic target for maintaining, losing, or gaining weight.
How it is calculated
This calculator uses the Mifflin-St Jeor equation, the most accurate formula for most people: for men, BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5; for women, BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. TDEE is then found by multiplying BMR by an activity factor: 1.2 for sedentary, 1.375 for light activity, 1.55 for moderate, 1.725 for very active, and 1.9 for extra active.
Reference ranges
Frequently asked questions
Why is my BMR lower than I expected?
BMR decreases with age and is generally lower for smaller bodies and people with less muscle mass. Strength training can gradually raise your BMR by increasing muscle, which burns more calories at rest than fat.
How accurate is the Mifflin-St Jeor equation?
It is the most reliable predictive equation for healthy adults, but individual variation means your true BMR may differ by 5–10%. Medical conditions like thyroid disorders can also affect your actual metabolic rate.
Should I eat below my BMR to lose weight?
Eating below your BMR is generally not advisable — your body needs that energy for vital functions. Instead, create a moderate deficit from your TDEE and focus on nutrient-dense foods.
Calories & BMR
Calculate your Basal Metabolic Rate — the calories your body burns at rest — using multiple established formulas.