Health📅 18 March 2025⏱ 6 min read
What Is TDEE? How to Calculate Your Daily Calorie Burn
TDEE is the number that defines whether you gain, lose, or maintain weight. Here's exactly what it means and how to calculate it accurately.
JW
James WhitfieldPersonal Finance & Maths WriterJames has written about personal finance, health metrics, and everyday mathematics for over six years. He holds a BSc in Mathematics from the University of Leeds.
TDEE — Total Daily Energy Expenditure — is the total number of calories your body burns in a day. It's the single most important number in any diet or body composition plan: eat below it to lose weight, above it to gain, and at it to maintain.
What Makes Up Your TDEE?
- BMR (60–75%): The calories your body burns to stay alive — breathing, circulation, cell repair. Even completely at rest, you'd burn your BMR.
- TEF (~10%): The energy cost of digesting food. Protein has the highest TEF (20–30%), then carbs (5–10%), then fat (0–3%).
- Exercise (variable): Calories burned during intentional workouts — the component most people overestimate.
- NEAT (15–30%): Non-Exercise Activity Thermogenesis — walking, fidgeting, standing, typing. Often varies by 500+ calories per day between individuals and is massively underestimated.
How to Calculate TDEE
Start with the Mifflin-St Jeor equation for BMR:
BMR (men) = 10W + 6.25H − 5A + 5BMR (women) = 10W + 6.25H − 5A − 161(W = kg · H = cm · A = age)
Then multiply by your activity factor:
Activity LevelDescriptionMultiplier
SedentaryDesk job, little movement× 1.2
Lightly active1–3 days/week exercise× 1.375
Moderately active3–5 days/week× 1.55
Very active6–7 days/week hard training× 1.725
Extra activePhysical job + daily training× 1.9
Using TDEE for Fat Loss
A 500 cal/day deficit creates roughly 0.5 kg weekly fat loss. Guidelines:
- Mild deficit (10–15%): Best for muscle retention. Sustainable long-term.
- Moderate (20–25%): Faster results. Requires higher protein to preserve muscle.
- Aggressive (>25%): Not recommended — increases muscle loss, metabolic adaptation, and nutrient deficiencies.
Why TDEE Changes Over Time
As you lose weight, your TDEE drops — a smaller body needs less energy. Recalculate every 4–6 weeks. NEAT also decreases during calorie restriction (you unconsciously move less), which can reduce effective TDEE by an additional 10–15% beyond what body weight alone predicts.