TDEE Calculator

Total daily energy expenditure is the full calorie cost of a day of your life, not just the cost of lying still. It is built from four parts: your basal metabolic rate, the energy used to digest food, the calories burned in deliberate exercise, and everything else you do without thinking — fidgeting, walking, standing, housework — collectively called non-exercise activity thermogenesis.

The simplest way to estimate it is to take your BMR and multiply it by an activity factor. Sedentary work with no exercise uses about 1.2 times BMR. Light activity — one to three sessions a week — uses 1.375. Moderate, three to five sessions, uses 1.55. Active, six to seven sessions, uses 1.725. Hard daily training uses around 1.9. The gap between the first and last step is enormous: the same person can have a maintenance requirement of 2,000 or 3,200 calories depending on which box they tick.

That is the honest limitation of the method. Activity multipliers are coarse, and most people either overestimate how active they are or underestimate how much they move. The number this calculator returns is a well-informed starting guess, not a measurement. The way to make it accurate is to use it for two to three weeks and then correct: if your weight is stable on the suggested maintenance figure, it is right for you. If you are losing weight when you expected to maintain, your true expenditure is higher, and vice versa.

Once you have a decent maintenance number, the rest is arithmetic. To lose fat, most people do well on a 10 to 20 percent deficit — roughly 300 to 600 calories below maintenance for an average adult — which supports steady loss without wrecking energy, training quality or sleep. To gain muscle, a surplus of about 10 percent is usually enough; larger surpluses mostly add fat. Resist the urge to cut harder or bulk faster: the extremes are where muscle loss, fatigue and rebound overeating live.

This calculator returns estimates for general information only. It is not medical advice, diagnosis or treatment, and it cannot replace an assessment by a qualified health professional. Individual results vary, and figures such as calorie needs, body-fat percentage and heart-rate zones are approximations based on population averages rather than measurements of you.