What is TDEE?
TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns over a 24-hour period. It is not just the calories burned during exercise — it captures every single energy-consuming process in your body, broken down into four components:
- BMRBasal Metabolic Rate — the calories burned at complete rest to sustain breathing, circulation, organ function, and body temperature. This makes up 60–75% of your TDEE.
- TEFThermic Effect of Food — the energy cost of digesting and metabolizing what you eat. Protein is the most thermogenic macro, costing 20–30% of its calories to process, vs 5–10% for carbs and 0–3% for fat.
- EATExercise Activity Thermogenesis — deliberate training sessions: lifting, running, cycling, etc.
- NEATNon-Exercise Activity Thermogenesis — everything else: walking, fidgeting, standing, household chores. NEAT varies enormously between individuals and is a major driver of why two people with the same BMR can have very different TDEEs.
Your TDEE is your maintenance calorie level — the exact intake where your weight stays stable. Every body transformation strategy is built relative to this number.
How the Mifflin-St Jeor Formula Works
Our calculator uses the Mifflin-St Jeor equation, validated in a 1990 landmark study and consistently outperforming the older Harris-Benedict formula in accuracy for modern populations. The formula for Basal Metabolic Rate (BMR) is:
Men: BMR = (10 × weight (kg)) + (6.25 × height (cm)) − (5 × age) + 5
Women: BMR = (10 × weight (kg)) + (6.25 × height (cm)) − (5 × age) − 161
TDEE = BMR × Activity Multiplier (1.2 – 1.9)
The activity multiplier accounts for everything beyond pure rest:
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | × 1.2 | Desk job, minimal walking |
| Lightly Active | × 1.375 | 1–3 light workouts per week |
| Moderately Active | × 1.55 | 3–5 moderate sessions per week |
| Very Active | × 1.725 | 6–7 intense training sessions per week |
| Elite Athlete | × 1.9 | Twice-daily training or physical labor job |
💡 Most people overestimate their activity level. If in doubt, choose one level lower and adjust after tracking for 2 weeks.
Using Your TDEE to Hit Your Goal
Once you know your TDEE, the path to your goal is straightforward:
Fat Loss
−500 kcal / day
Creates a ~0.5 kg/week deficit. Pair with high protein to protect muscle.
Maintenance
± 0 kcal
Body recomposition — slowly replacing fat with muscle over time.
Muscle Gain
+200–300 kcal
Lean surplus minimizes fat gain while providing energy for hypertrophy.
For precise macro targets within your calorie budget, use our macro calculator — it builds on your TDEE to split calories into the optimal protein, carb, and fat ratios for your goal.
Why TDEE Estimates Are Never Perfect
No equation can perfectly account for your unique biology. Key variables that the calculator cannot measure include:
- →Muscle-to-Fat Ratio: Muscle tissue burns ~3× more calories at rest than fat. Two people at identical weight and height can have BMRs that differ by 200+ kcal if one is significantly more muscular.
- →Metabolic Adaptation: Prolonged calorie restriction causes the body to downregulate NEAT and thyroid output — effectively lowering your real TDEE below what the formula predicts.
- →Hormonal Profile: Thyroid disorders, cortisol levels, and insulin sensitivity all influence how efficiently your body burns fuel.
- →Gut Microbiome: Emerging research suggests microbial composition affects how many calories are actually absorbed from food.
The practical solution: use the calculator output as your starting point, eat at that number for exactly 2 weeks while tracking daily weight, then adjust by 100–200 kcal based on the trend. This empirical approach is more accurate than any formula alone.
Frequently Asked Questions
Should I eat back calories burned from exercise?
Not if you used the correct activity multiplier. If you selected 'Moderately Active' (3–5 sessions/week), your TDEE already includes those burned calories. Only eat back exercise calories if you chose Sedentary but then trained unexpectedly.
Why is my TDEE different on other calculators?
Different sites use different formulas (Harris-Benedict, Katch-McArdle, Cunningham). We use Mifflin-St Jeor because it is the most validated for the general population. Small differences in rounding and activity multipliers also account for discrepancies.
How often should I recalculate my TDEE?
Recalculate every 4–8 weeks, or any time your weight changes by more than 5 kg. As you lose fat or gain muscle, your BMR shifts — your old TDEE number becomes less accurate. Most people hitting a plateau simply haven't updated their targets.
🔥 Related Fitness Calculators
Your TDEE is step one. These tools complete the picture.