What Is TDEE?
Total Daily Energy Expenditure (TDEE) is the total number of calories your body burns in 24 hours, encompassing everything from keeping your heart beating while you sleep to the energy cost of your afternoon run. Understanding your TDEE is the single most important step in managing your body weight, because all weight change ultimately comes down to the relationship between calories consumed and calories burned.
TDEE has four components:
- BMR (Basal Metabolic Rate) — the calories burned at complete rest, just to maintain organ function. Typically 60–75% of TDEE.
- NEAT (Non-Exercise Activity Thermogenesis) — calories burned through all non-exercise movement: walking, fidgeting, doing chores. Hugely variable between individuals.
- EAT (Exercise Activity Thermogenesis) — calories burned during deliberate exercise.
- TEF (Thermic Effect of Food) — calories used to digest, absorb, and metabolise food. Roughly 10% of total calorie intake for a mixed diet.
How to Calculate Your TDEE
The standard approach uses a two-step process:
Step 1: Calculate Your BMR
Use the Mifflin-St Jeor equation, the most validated formula for general adults:
- Men: BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) + 5
- Women: BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) − 161
Example: A 35-year-old woman, 68 kg, 170 cm:
BMR = (10 × 68) + (6.25 × 170) − (5 × 35) − 161 = 680 + 1062.5 − 175 − 161 = 1,406.5 kcal/day
Step 2: Multiply by Your Activity Factor
| Activity Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, minimal exercise |
| Lightly active | 1.375 | 1–3 days of light exercise/week |
| Moderately active | 1.55 | 3–5 days moderate exercise/week |
| Very active | 1.725 | Hard exercise 6–7 days/week |
| Extremely active | 1.9 | Physical job + daily intense training |
Continuing the example: If she exercises 3–5 days per week (moderately active):
TDEE = 1,406.5 × 1.55 = 2,180 kcal/day
This means she burns approximately 2,180 calories per day on average and needs to eat at this level to maintain her current weight.
Setting a Calorie Target for Weight Loss
One pound (0.45 kg) of body fat stores approximately 3,500 kcal. To lose fat at a predictable rate, create a daily calorie deficit below your TDEE:
- 250 kcal/day deficit → ~0.23 kg (0.5 lb) per week — very gentle, sustainable long-term
- 500 kcal/day deficit → ~0.45 kg (1 lb) per week — the most commonly recommended rate
- 750 kcal/day deficit → ~0.68 kg (1.5 lbs) per week — aggressive, suitable for short periods only
For the example above: 2,180 − 500 = 1,680 kcal/day for moderate fat loss of about 2 kg per month.
Important floor: Do not eat below 1,200 kcal/day (women) or 1,500 kcal/day (men) without medical supervision. Very low calorie diets cause muscle loss, micronutrient deficiencies, metabolic adaptation, and are not sustainable.
How to Verify Your TDEE
The Mifflin-St Jeor formula is accurate within ±10–15% for most people. But individual metabolism varies. The only way to verify your real TDEE is to track:
- Weigh yourself daily (first thing in the morning, same conditions) for 14 days.
- Log every calorie you eat as accurately as possible (use a food scale, not estimates).
- Calculate your average daily intake over those 14 days.
- If your weight stayed flat, your real TDEE ≈ your average intake. If you gained, your real TDEE is lower; if you lost, it is higher.
This two-week calibration period is far more accurate than any formula because it accounts for your individual metabolic rate, NEAT patterns, and measurement habits.
Common TDEE Mistakes
- Overestimating activity level. Most people who describe themselves as "moderately active" are actually lightly active. When in doubt, choose the lower multiplier and adjust upward if you are losing weight faster than expected.
- Not recalculating as weight changes. As you lose weight, your BMR decreases because you are carrying less mass. Recalculate every 4–6 kg of weight change.
- Underestimating calories consumed. Studies show most people underestimate intake by 20–50%. Use a kitchen scale for at least 2–4 weeks to calibrate your estimating ability.
- Ignoring liquid calories. Coffee with cream, juice, and alcohol add significant calories that are easy to overlook.
TDEE for Muscle Gain
To build muscle, you need a calorie surplus above TDEE. A modest surplus of 200–400 kcal/day ("lean bulk") maximises muscle growth while minimising fat gain. Larger surpluses add fat proportionally faster without meaningfully accelerating muscle growth beyond a certain point.
Try the CalcDash TDEE Calculator
Our free TDEE Calculator uses the Mifflin-St Jeor equation to calculate your BMR and TDEE, then shows calorie targets for fat loss, maintenance, and muscle gain. Enter your stats and get your numbers in seconds — no signup required.