Total Daily Energy Expenditure (TDEE) is an estimate of the total number of calories an individual burns in a 24-hour period. It combines an individual's [basal metabolic rate](bmr) with the energy expended through physical activity and food digestion. TDEE represents the caloric intake required to maintain current body weight.
Formula
TDEE = BMR × Activity Factor
Where BMR is calculated via formulas like Mifflin-St Jeor:
BMR (men) = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in yrs) + 5
BMR (women) = (10 × weight in kg) + (6.25 × height in cm) - (5 × age in yrs) - 161
Activity Factors: Sedentary (1.2), Lightly Active (1.375), Moderately Active (1.55), Active (1.725), Very Active (1.9).How to interpret it
Your TDEE serves as the baseline energy target for body composition management. Consuming calories equal to your TDEE maintains your current body weight. To achieve weight loss, subtract 500 kcal per day from your calculated TDEE to establish a safe [caloric deficit](caloric-deficit) targeting approximately 1 lb (0.45 kg) of fat loss per week. To gain lean muscle mass, add 250–500 kcal per day to create a caloric surplus (Fitulse's calculator uses a 300 kcal daily surplus). Because mathematical estimations carry an intrinsic variance of 10–15%, evaluate your calculated TDEE over a 2–4 week tracking period using a daily body weight average. If weight remains static during an intended loss phase, reduce intake by 100–200 kcal increments. Always recalculate your TDEE when your total body weight changes by a 5% weight recalculation threshold, as metabolic output changes alongside body mass.
Worked example
Consider a 30-year-old female weighing 65 kg (143 lbs) at 165 cm tall, with a moderately active lifestyle. 1. Calculate BMR using Mifflin-St Jeor: (10 × 65) + (6.25 × 165) - (5 × 30) - 161 = 650 + 1031.25 - 150 - 161 = 1,370.25 kcal (rounded to 1,370 kcal in the tool). 2. Multiply BMR by the moderately active activity factor (1.55): 1,370.25 × 1.55 = 2,123.89 kcal (rounded to 2,124 kcal TDEE). 3. Daily target application: Her maintenance TDEE is approximately 2,124 kcal. To target weight loss, she applies a 500 kcal deficit, yielding a daily calorie target of 1,624 kcal.
Limitations
TDEE calculations utilize standardized activity multipliers that frequently fail to capture individual metabolic variability. The thermic effect of food (TEF) fluctuates based on macronutrient ratios, as dietary protein requires significantly more energy to break down than fats or carbohydrates. Non-exercise activity thermogenesis (NEAT)—spontaneous movements like fidgeting, posture maintenance, and casual walking—can vary between two people of identical size by up to 800 kcal per day. Standard TDEE formulas also overestimate calorie expenditure in individuals with elevated body fat percentages or low muscle mass, as adipose tissue is less metabolically active than lean tissue. Furthermore, metabolic adaptation during sustained caloric restriction can systematically reduce actual energy expenditure below predicted estimates.
FAQ
How often should I recalculate my TDEE?
Recalculate your TDEE after reaching a 5% weight recalculation threshold (e.g., losing or gaining 5% of your total weight), or whenever your daily job duties or structured exercise habits permanently change.
Why am I not losing weight while eating at my calculated caloric deficit?
Calculated TDEE metrics are initial estimates. Inaccurate portion measuring, unrecorded snacks, or subconscious reductions in non-exercise movement (NEAT) often eliminate a target 500 kcal deficit. Track your weight across a 2–4 week tracking period before adjusting daily targets down by 100–200 kcal.
Does building muscle increase my TDEE?
Yes. Skeletal muscle tissue burns roughly 13 kcal per kilogram per day at rest, compared to adipose tissue which burns roughly 4.5 kcal per kilogram. Increasing muscle mass raises your baseline [BMR](bmr), which subsequently elevates your TDEE.