For educational and tracking purposes only. Results are estimates and are not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional.
Calculator tool
How this calculator works
Use the explanation to understand the formula, assumptions, and practical limits behind the calculator result.
What Is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in a day — at rest and through all movement. It is the number that determines whether you gain, lose, or maintain weight. Eating above TDEE produces a surplus; below it produces a deficit.
TDEE has four components:
- BMR (60–75%): calories burned at complete rest
- Exercise activity (15–30%): structured workouts
- NEAT (Non-Exercise Activity Thermogenesis, 10–15%): walking, fidgeting, standing, casual movement
- Thermic Effect of Food (~10%): calories burned digesting and processing food
The Calculation
Step 1 — BMR (Mifflin-St Jeor):
Where = weight in kg, = height in cm, = age in years.
Men:
Women:
Step 2 — Apply activity multiplier:
| Activity Level | Multiplier | What It Means |
|---|---|---|
| Sedentary | ×1.2 | Desk job, no exercise |
| Lightly active | ×1.375 | Exercise 1–3 days/week |
| Moderately active | ×1.55 | Exercise 3–5 days/week |
| Very active | ×1.725 | Exercise 6–7 days/week |
| Extra active | ×1.9 | Physical job or 2× daily training |
Worked Example
Inputs: Male, age 35, weight 80 kg, height 178 cm, moderately active
BMR: kcal
TDEE: kcal/day
Weight loss target (−500 kcal): kcal/day
Weight gain target (+250 to +500 kcal): to kcal/day
Now switch to sedentary: kcal. The same person sitting at a desk instead of exercising regularly burns 610 fewer calories per day.
How to Read Your TDEE
- Eating at TDEE: weight maintenance
- 500 kcal below TDEE: ~0.45 kg (1 lb) fat loss per week
- 250–500 kcal above TDEE: a gradual weight-gain target; how much becomes lean mass depends on training, protein, recovery, and genetics
- 250 kcal below TDEE: slower, more sustainable loss with less risk of lean mass catabolism
TDEE from a formula has a standard deviation of roughly ±300 kcal. The activity multiplier is the largest source of error — people consistently overestimate their activity level. If body weight is not responding as expected after 2–3 weeks, adjust calories by 100–200 kcal rather than recalculating from scratch.
When to Recalculate
Recalculate TDEE whenever: you change activity level significantly, you lose or gain more than 5 kg, or your progress stalls for more than 2 weeks. A 10% weight loss typically reduces TDEE by 10–15%, so a fixed calorie target gradually becomes inaccurate.
Common Mistakes
Selecting an activity level that reflects your gym sessions but not your desk job. TDEE captures total daily movement. A person who trains hard but sits for 10 hours daily is typically moderately active at most — not very active.
Using TDEE as a precise measurement. It is an estimate with real error margins. Track and adjust based on actual outcomes, not just the formula output.
Frequently asked questions
How is TDEE different from BMR?
BMR is calories burned at complete rest — the energy to keep organs functioning if you lay still all day. TDEE adds everything on top: exercise, walking, standing, fidgeting, and the energy used to digest food.
For a sedentary person, TDEE ≈ BMR × 1.2 (about 20% above BMR). For someone very active, TDEE can reach BMR × 1.9. This means activity level can account for a 400–800 kcal difference in daily energy needs at the same body size.
Why is TDEE only an estimate, not an exact number?
TDEE formulas have a standard deviation of roughly ±200–300 kcal. The sources of error stack up: the BMR equation has ~10% error for most people; activity multipliers are averages across populations, not individual measurements; and self-reported activity level is consistently overestimated by 30–50%.
The most accurate way to find your real TDEE is to track food intake precisely for 2–3 weeks while monitoring weight change. If weight is stable, your average intake equals your TDEE. If it is moving, add or subtract the calorie equivalent to determine true maintenance.
How does switching activity levels change TDEE?
Each step up the activity multiplier scale adds 10–20% to BMR. Moving from sedentary (×1.2) to moderately active (×1.55) on a 1,700 kcal BMR adds kcal/day.
This is why activity level is the single most impactful variable in TDEE after body size. A one-level increase in activity (e.g., from sedentary to lightly active) has a larger calorie impact than most dietary adjustments.
When should I recalculate my TDEE?
Recalculate whenever there is a meaningful change in the inputs: a 5 kg or greater weight change, a shift in activity level (starting or stopping a training program), a significant age milestone, or a change in physical job demands.
Also recalculate if your body weight is not responding as expected after 2–3 weeks of consistent tracking. Stalled progress usually means actual energy balance differs from the estimate. The most common cause is overestimating activity level, but food tracking error, water retention, sleep, medication, and menstrual-cycle changes can also hide short-term progress.
