How we calculate your calories
This calculator uses the Mifflin-St Jeor equation, considered the most accurate BMR formula by the Academy of Nutrition and Dietetics:
Men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5
Women: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age − 161
Your BMR (Basal Metabolic Rate) is multiplied by an activity factor to get your TDEE (Total Daily Energy Expenditure) — the calories you burn in a typical day including exercise.
A pound of fat is roughly 3,500 calories. To lose 1 lb/week, you need a deficit of about 500 calories/day. To gain 1 lb/week, you need a surplus of about 500 calories/day.
Use calorie estimates as a starting point
A calorie calculation is an estimate, not a prescription. Equations use information such as age, height, weight, sex, and reported activity, but they cannot perfectly capture metabolism, medical conditions, medication effects, training volume, or day-to-day movement.
For a practical approach, choose one target, follow it consistently for a few weeks, and observe how your energy, hunger, performance, and weight trend respond. Adjust gradually rather than making large changes based on a single day or weigh-in. Protein, fiber, sleep, and strength training can matter alongside the calorie total.
People who are pregnant, breastfeeding, under 18, managing an eating disorder, or living with a medical condition should get individualized guidance from a qualified clinician or dietitian. This calculator provides general education and is not medical or nutrition advice.
See How Daily Calorie Needs Are Estimated for an explanation of BMR and activity levels.