TDEE Calculator
Quick answer: TDEE (total daily energy expenditure) is your maintenance calories: BMR from the Mifflin-St Jeor equation multiplied by an activity factor from 1.2 (sedentary) to 1.9 (athlete). Eat ~500 below it to lose about a pound a week, ~300 above it to lean bulk.
How to actually use this number
Pick one goal number (cut, maintain or bulk), eat within ±100 calories of it consistently, and weigh yourself under the same conditions a few times a week. The weekly average trend — not any single day — tells you if your real-world TDEE matches the estimate. Adjust in 150-200 calorie steps.
TDEE and GLP-1 medications
Appetite-suppressing medications make it easy to eat far below TDEE without noticing, which accelerates muscle loss. If you're on semaglutide or tirzepatide, knowing your TDEE helps you keep the deficit deliberate (500-750 kcal) rather than accidental (1,200+), and our protein calculator gives the intake that protects lean mass.
FAQ
Which TDEE formula is most accurate?+
Mifflin-St Jeor (used here) is the best-validated equation for the general population, outperforming the older Harris-Benedict formula in studies. All equations are ±10% estimates — two weeks of tracking weight against intake beats any calculator.
Why am I not losing weight at my calculated deficit?+
The usual suspects: activity level overestimated (most people pick one tier too high), untracked calories (oils, drinks, weekends), and water retention masking early fat loss. Recalculate with the lower activity tier and give any change three weeks before judging.
Does TDEE change as I lose weight?+
Yes — a lighter body burns fewer calories, and adaptation adds a further small drop. Recalculate every 10 lb (5 kg) of change, or whenever a previously working deficit stalls for 3+ weeks.
Educational tool — estimates only, not medical advice. Consult a licensed healthcare provider for individual guidance.