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TDEE Calculator: What It Is and How to Use It for Weight Loss

·7 min read
TDEEBMRcalorie calculator

What Is TDEE?

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a 24-hour period. It accounts for everything from breathing and digesting food to walking and exercising.

Your TDEE is made up of four components:

Component% of TDEEDescription
BMR60–70%Calories burned at complete rest
NEAT15–20%Non-exercise activity (walking, fidgeting, standing)
TEF8–10%Energy to digest and absorb food
EAT5–10%Deliberate exercise
Understanding your TDEE is the foundation of any successful diet plan — whether you want to lose fat, build muscle, or maintain your weight.

How Is TDEE Calculated?

Step 1: Calculate BMR

The most accurate widely-used formula is the Mifflin-St Jeor equation:

  • Men: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) + 5
  • Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161

Step 2: Multiply by Activity Factor

Activity LevelMultiplierDescription
Sedentary1.2Desk job, little exercise
Lightly active1.375Light exercise 1–3 days/week
Moderately active1.55Moderate exercise 3–5 days/week
Very active1.725Hard exercise 6–7 days/week
Extremely active1.9Intense exercise + physical job
Example: A 28-year-old man, 180cm, 85kg, moderately active:
  • BMR = (10 × 85) + (6.25 × 180) − (5 × 28) + 5 = 1,835 kcal
  • TDEE = 1,835 × 1.55 = 2,844 kcal/day

How to Use TDEE for Your Goals

Weight Loss

Eat below your TDEE to create a calorie deficit:
  • Subtract 300–500 kcal for steady fat loss (0.3–0.5kg/week)
  • Subtract 500–750 kcal for faster results (0.5–0.75kg/week)

Muscle Gain

Eat above your TDEE to provide surplus energy for muscle growth:
  • Add 200–300 kcal for lean bulking
  • Add 400–500 kcal for faster mass gain

Maintenance

Eat at your TDEE to stay the same weight. This is useful for:
  • Diet breaks (to reset hunger hormones)
  • Body recomposition (lose fat and gain muscle simultaneously at a slow pace)

Common TDEE Mistakes

  1. Overestimating activity level — Most people are less active than they think. If in doubt, choose one level lower.
  2. Not recalculating — Your TDEE changes as your weight, age, and activity change. Recalculate every 4–6 weeks.
  3. Ignoring NEAT — Non-exercise activity (steps, fidgeting, housework) can vary by 500+ calories between people. This is why some people seem to "eat whatever they want."
  4. Using outdated formulas — The Harris-Benedict equation (1919) is less accurate than Mifflin-St Jeor (1990). Make sure your calculator uses the modern formula.

Why CalCalc Uses Mifflin-St Jeor

CalCalc AI defaults to the Mifflin-St Jeor equation because peer-reviewed research consistently shows it's the most accurate for the general population — within 10% of measured BMR for most people.

For those who know their body fat percentage, CalCalc also supports the Katch-McArdle formula, which accounts for lean body mass and can be more accurate for very lean or very overweight individuals.

Calculate Your TDEE Now

Use CalCalc's free TDEE calculator to find your personalised daily calorie target. You'll get:

  • Your BMR and TDEE
  • Calorie targets for weight loss, maintenance, and muscle gain
  • A personalised macro breakdown (protein, carbs, fat)
  • A goal timeline showing when you'll reach your target weight

No sign-up required — just enter your details and get instant results.