TDEE Calculator – How Many Calories Should I Eat Per Day?

How many calories per day—and why it is not one number forever

Your daily energy expenditure shifts with weight, muscle, age, sleep, stress, and job type. Treat TDEE as a starting estimate you validate over 2–4 weeks of weight and performance trends. The TDEE calculator uses Mifflin–St Jeor for BMR and standard activity multipliers.

BMR vs TDEE in plain language

BMR is the energy to “keep the engine idling”—organs, brain, temperature. TDEE adds walking, work, training, digestion, and fidgeting. If intake sits below TDEE in a moderate range, weight usually trends down; above TDEE, it trends up.

Deficit and surplus without extremes

For many people, a sustainable deficit is about 250–500 kcal under TDEE; more aggressive cuts deserve medical oversight. For muscle gain, a common surplus is roughly 200–350 kcal over TDEE with strength training and adequate protein.

How to use the calculator

1. Enter sex, age, height, and a honest morning weight.
2. Pick an activity tier that matches the whole day, not only the gym.
3. Note maintenance TDEE and suggested targets.
4. After two weeks, adjust by ~100–150 kcal if trends stall.

Common mistakes

• Labeling three gym hours as “very active” while the rest of the day is desk-bound.
• Ignoring sleep, which changes appetite and expenditure.
• Chasing calories alone without protein and strength work during a cut.

Related tools

Macro calculator · 1RM calculator · Longer TDEE explainer