Estimate how many calories you burn in a normal day (TDEE) from your age, sex, weight, height and activity level. Use it to set a realistic diet or bulking target.
The calculator finds BMR with the Mifflin-St Jeor equation, then multiplies by an activity factor to get TDEE — the calories you burn on a normal day. Eat below TDEE to lose, above to gain.
Guessing "eat less" fails because the target is unknown. A number tied to your body and lifestyle turns weight goals into a measurable plan.
Cutting too hard. A deficit beyond ~1,000 kcal/day often costs muscle and stalls metabolism; a moderate 300–500 kcal gap loses fat while keeping energy up.
Is TDEE exact? It is an estimate; wearables and scales refine it, but it is accurate enough to start.
Do I count exercise calories? If you log workouts separately, use the sedentary factor and add exercise, or you double-count movement.