Your Total Daily Energy Expenditure (TDEE) is the single most useful number in nutrition planning. It tells you how many calories you burn in a day, which is the anchor for any fat-loss, maintenance or muscle-building plan.
What is TDEE?
TDEE is the sum of every calorie your body spends in a day. It has four components: your Basal Metabolic Rate (BMR, ~60–70%), the Thermic Effect of Food (~10%), exercise activity, and Non-Exercise Activity Thermogenesis (NEAT) — everything from walking to fidgeting.
How is it calculated?
We first estimate BMR with the Mifflin–St Jeor equation, then multiply by an activity factor from 1.2 (sedentary) to 1.9 (athlete). The result is your maintenance calorie level.
The formula
BMR (men) = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5. BMR (women) uses −161 instead of +5. TDEE = BMR × activity factor.
Common mistakes
The biggest error is over-estimating activity level — most people who 'work out 5 days a week' still fall closer to 'lightly active' across a full 24-hour day. When in doubt, pick the lower multiplier and adjust up.
Frequently asked questions
Total Daily Energy Expenditure is the total calories your body uses in 24 hours, including your basal metabolic rate, digestion, daily movement and exercise.
We use the Mifflin–St Jeor equation to estimate BMR, then apply a standard activity multiplier. It's the most accurate general-population predictive equation validated in research.
Predictive equations are typically within ~10% for most people. Use the number as a starting point and refine it by tracking your actual weight trend over 2–3 weeks.
Generally no. A moderate deficit from your TDEE preserves muscle and is far easier to sustain than very-low-calorie dieting.