What Is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day – everything from keeping your heart beating and lungs breathing to digesting food and exercising.
Understanding your TDEE is the starting point for any informed nutrition strategy. Eat consistently below it and you lose weight. Eat above it and you gain. Match it and you maintain. The rest – macro splits, meal timing, food quality – matters, but it matters less than this fundamental energy balance equation.
The Four Components of TDEE
1. BMR (Basal Metabolic Rate) – the calories your body burns at complete rest: organ function, cell repair, temperature regulation. BMR accounts for 60–70% of TDEE for most people.
2. TEF (Thermic Effect of Food) – the energy cost of digesting, absorbing, and processing the food you eat. Roughly 10% of total calorie intake. Protein has the highest TEF (20–30%); fat the lowest (0–3%).
3. NEAT (Non-Exercise Activity Thermogenesis) – calories burned through all movement that is not formal exercise: walking to your car, fidgeting, household tasks, standing at your desk. Highly variable – sedentary people burn very little; active people can burn 500+ extra calories per day through NEAT alone.
4. EAT (Exercise Activity Thermogenesis) – calories burned during planned exercise sessions. Runners, cyclists, and regular gym-goers see this component vary substantially by training volume.
How to Estimate Your TDEE
Step 1: Calculate BMR
The two most accurate widely used formulas are:
Mifflin-St Jeor (preferred):
- Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
- Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Harris-Benedict (original, older):
- Men: BMR = 88.362 + (13.397 × kg) + (4.799 × cm) − (5.677 × age)
- Women: BMR = 447.593 + (9.247 × kg) + (3.098 × cm) − (4.330 × age)
Step 2: Apply an Activity Multiplier
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | × 1.2 | Desk job, little movement |
| Lightly active | × 1.375 | Light exercise 1–3 days/week |
| Moderately active | × 1.55 | Moderate exercise 3–5 days/week |
| Very active | × 1.725 | Hard exercise 6–7 days/week |
| Extremely active | × 1.9 | Physical job + daily hard training |
Using TDEE for Your Goals
Weight loss: Eat 300–500 calories below TDEE daily. This creates a sustainable deficit that produces ~0.3–0.5 kg loss per week without excessive muscle loss or metabolic adaptation. Deficits larger than 1,000 calories/day are not recommended for most people.
Muscle gain: Eat 200–350 calories above TDEE (a "lean bulk"). Larger surpluses increase muscle gain marginally but accelerate fat accumulation significantly.
Maintenance: Match TDEE. This is harder than it sounds – TDEE is an estimate, and actual expenditure varies day to day.
Why TDEE Estimates Are Not Perfect
TDEE formulas are validated on population averages and have an error margin of roughly ±10–15% for any individual. Factors that reduce accuracy:
- Metabolic adaptation: prolonged calorie restriction lowers BMR as the body adapts
- Hormone variation: thyroid function, insulin sensitivity, and cortisol all affect energy expenditure
- Activity multipliers are self-reported: people consistently overestimate their activity level
Treat your calculated TDEE as a starting point. Track intake and weight for 2–3 weeks, then adjust based on actual results – not the formula.
Calculate Your TDEE
The TDEE & Calorie Calculator on this site computes your BMR using the Mifflin-St Jeor formula, applies your activity multiplier, and gives you calorie targets for weight loss, maintenance, and muscle gain – all in your browser with no account required.
Summary
TDEE is the total calories you burn per day. It is calculated from BMR (resting metabolism) multiplied by an activity factor. Use it as a baseline for dietary planning – but treat it as an estimate and adjust based on real-world results over 2–3 weeks.