TDEE estimates: resting energy plus daily activity
Total daily energy expenditure is an estimate of the energy your body uses over a day. This calculator first applies the Mifflin–St Jeor resting-energy equation, labelled BMR on the page, then multiplies it by an activity factor. Enter age, the equation's sex category, weight in kilograms and height in centimetres. The result is a starting estimate for adult energy needs, not a measurement of metabolism or a personalised diet prescription. Individual energy use varies with body composition, daily movement and medical circumstances.
The equation and activity assumptions
The male equation is 10 × weight + 6.25 × height − 5 × age + 5. The female equation is 10 × weight + 6.25 × height − 5 × age − 161. Weight is in kg, height in cm and age in years. Multiply this resting estimate by the selected factor: sedentary 1.2, light 1.375, moderate 1.55, active 1.725 or athlete 1.9.
The original equation predicts resting energy expenditure. Activity factors are separate assumptions, not precise measurements validated for your daily routine by entering a workout count. A desk job with several brief workouts may still involve little movement during the rest of the week. Choose an honest overall activity estimate rather than automatically picking a high factor.
Use the estimate cautiously
The page also shows maintenance, a 500 kcal subtraction and a 300 kcal addition. These are arithmetic scenarios, not universally appropriate intake targets. They do not guarantee a weekly weight change. Do not add exercise calories again if the activity factor already includes those workouts; that can count the same movement twice.
Review energy, performance and weight trends over time instead of assuming one calculated value is exact. Food tracking, water retention and wearable estimates also have uncertainty. Children, pregnancy, breastfeeding, eating disorders and medical conditions need individual professional guidance rather than this adult equation. Do not use an online estimate to justify extreme restriction. Seek a qualified clinician or registered dietitian when deciding on a substantial change in intake.
Worked examples
30-year-old male, 70 kg, 175 cm
Resting estimate = 700 + 1,093.75 − 150 + 5 = 1,648.75 kcal/day. At the moderate 1.55 factor, TDEE = 2,555.56, displayed as about 2,556 kcal/day. This is an estimate, not a measured calorie requirement.
The same inputs, sedentary factor
Using 1.2 instead gives 1,978.50 kcal/day, approximately 1,979. The roughly 577 kcal difference shows how much the activity assumption affects the result without any change in age, height or weight.
Frequently asked questions
Is BMR the same as measured metabolism?
No. The displayed BMR is an equation-based resting-energy estimate. Direct measurement requires controlled testing.
Should I add my workout calories?
Not if those workouts are already included in the selected activity factor. Adding them again would double-count activity.
Will the weight-loss scenario guarantee a result?
No. It is a simple subtraction from estimated TDEE, not a clinical recommendation or a guaranteed rate of weight change.
Is this suitable during pregnancy?
No. Pregnancy and breastfeeding need individual guidance; this adult estimate does not account for those energy needs.