How this calculator works
TDEE, or Total Daily Energy Expenditure, is the number most people actually want when they search for their 'calorie needs' — it is your resting burn (BMR) plus everything else you do in a day, and it is the figure to eat around for weight loss, maintenance, or gain. This calculator estimates BMR with the Mifflin-St Jeor equation, then scales it by your activity level to get TDEE.
This page focuses on TDEE and calorie planning specifically. If you want the resting-metabolism number on its own, with more detail on the Mifflin-St Jeor equation itself and why it is preferred over older formulas, see the dedicated BMR calculator. Here, the emphasis is the activity multiplier and the calorie table for cutting, maintaining, or bulking around your TDEE. These figures are estimates for general planning, not medical advice — talk to a doctor or dietitian before making major changes to your diet, especially if you have a health condition or a history of disordered eating.
The formula
Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161TDEE = BMR × activity factor (1.2 sedentary … 1.9 extra active)The activity factor is a rough multiplier, not a precise measurement — most people are closer to sedentary or lightly active than they think.
Worked example: man, 30, 80 kg, 180 cm, moderately active
- BMR = 10×80 + 6.25×180 − 5×30 + 5 = 800 + 1,125 − 150 + 5 = 1,780 kcal/day.
- Moderate activity (training 3–5 days a week) uses a 1.55 factor.
- TDEE = 1,780 × 1.55 ≈ 2,759 kcal/day to maintain current weight.
- A common -10% cut for gradual fat loss is about 2,483 kcal/day; a common +10% lean-gain surplus is about 3,035 kcal/day.
Frequently asked questions
How is TDEE different from BMR?
BMR is calories burned at complete rest. TDEE adds everything else: walking, chores, exercise, fidgeting. TDEE is always higher than BMR and is the number to actually plan meals around.
How many calories should I eat to lose weight?
A deficit of roughly 10-20% below TDEE is common practice for steady fat loss without excessive muscle loss or hunger; a 500 kcal/day deficit (which lands in that range for most people) gives about 1 lb (0.45 kg) per week. These percentages are general guidance, not a medical prescription — larger or more aggressive deficits should be discussed with a professional.
How many calories should I eat to build muscle?
A surplus of about 10-20% above TDEE is widely used practice for lean muscle gain while limiting fat gain. Larger surpluses build muscle faster only up to a point and mostly add fat beyond it.
Why do two TDEE calculators give me different numbers?
Differences usually come from the BMR equation used (Mifflin-St Jeor vs. older Harris-Benedict) and how loosely 'moderately active' is defined. Treat any TDEE estimate as a starting point and adjust it after two to three weeks based on what actually happens to your weight.
Does TDEE change as I lose or gain weight?
Yes. TDEE depends on body weight, so it drops as you lose weight and rises as you gain it. Recalculate every 10-15 lb (4-7 kg) of change, or every few months.