TDEE Calculator

What is TDEE and why it matters

Your Total Daily Energy Expenditure (TDEE) is the number of calories your body burns in a full day — the sum of your Basal Metabolic Rate (BMR), the energy cost of digesting food, and all movement from workouts to walking to the printer. Every fat-loss or muscle-gain plan starts here: eat below TDEE and you lose weight, eat above it and you gain. Without knowing this number you are guessing.

This calculator estimates BMR with the Mifflin-St Jeor equation, which validation studies rank as the most accurate of the common prediction formulas for the general population, then multiplies it by an activity factor from 1.2 (sedentary desk job, little exercise) to 1.9 (hard daily training plus a physical job).

How to use your result

Your maintenance number is the anchor. For sustainable fat loss, the calculator shows a 15–20% deficit — large enough to produce roughly 0.5 kg (1 lb) per week for most people, small enough to preserve muscle and stay livable. For muscle gain, a 5–10% surplus keeps most of the gain lean. Aggressive crash deficits backfire: they raise hunger hormones and burn muscle along with fat.

Enter a goal weight and the built-in Goal Date Predictor projects the calendar date you will reach it at the recommended deficit — turning an abstract number into a deadline. Recalculate every 4–6 weeks or after every 5 kg of weight change, because TDEE falls as you get lighter.

Desk workers should resist the urge to pick a flattering activity level: if your job is seated and you train 3 times a week, "Lightly Active" or "Moderately Active" is honest. Overestimating activity is the single most common reason calculated deficits fail to show up on the scale.

One caveat worth knowing: TDEE is not a fixed property of your body. Non-exercise activity thermogenesis (NEAT) — fidgeting, walking, standing, gesturing — varies by hundreds of calories a day between individuals, and it quietly falls when you diet, which is a large part of why weight loss decelerates. You can defend against that by making NEAT deliberate: a daily step target, a walk after meals, or a standing desk block keeps the number from drifting down while you are in a deficit. Once you have your target, use the Macro calculator to split those calories into protein, carbs and fat, since the calorie number alone does not determine whether the weight you lose is fat or muscle.