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TDEE vs BMR -- What’s the Difference?
Published May 1, 2026
TDEE vs BMR — What's the Difference?
BMR (Basal Metabolic Rate) and TDEE (Total Daily Energy Expenditure) are the two calorie figures that underpin virtually every nutrition and fat-loss plan. Understanding the difference — and when to use each — is the first step to setting realistic calorie targets.
BMR: calories at absolute rest
BMR is the energy your body burns doing nothing — breathing, keeping organs running, regulating temperature, and repairing cells. It is measured (or estimated) under strict lab conditions: lying still, fasted, at a comfortable temperature.
The most widely used estimation formula is Mifflin-St Jeor:
- Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) + 5
- Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) − 161
For a 30-year-old male weighing 75 kg at 178 cm: BMR ≈ 1,761 kcal/day
TDEE: calories in real life
TDEE multiplies BMR by an activity factor that accounts for movement, exercise, and the small caloric cost of digesting food (thermogenesis):
| Activity level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, little or no exercise |
| 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 |
| Extra active | 1.9 | Physical job + training twice daily |
Using the example above: TDEE at "moderately active" = 1,761 × 1.55 ≈ 2,730 kcal/day
Using BMR and TDEE for goals
Maintenance: Eat at TDEE. Weight should hold stable over weeks.
Fat loss (cutting): Target TDEE minus 300–500 kcal/day. This creates a deficit without collapsing energy, training output, or sleep quality. Larger deficits (500–750 kcal) are common but increase the risk of muscle loss and fatigue.
Muscle gain (bulking): Target TDEE plus 200–400 kcal/day — a modest surplus that limits fat gain while giving muscles the raw material to grow.
Why TDEE estimates are imperfect
Activity multipliers are averages. Real TDEE varies with:
- Non-exercise activity thermogenesis (NEAT) — fidgeting, walking, standing
- Metabolic adaptation after prolonged deficits
- Muscle mass: more lean mass raises BMR meaningfully
Use TDEE as a starting point, track your weight trend for 2–3 weeks, then adjust intake by 100–200 kcal in the direction you want.
Run numbers on the BMR & TDEE Calculator and check activity-specific calorie burn on the Calorie Counter.