What is TDEE?
TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day — including resting metabolism, digesting food, daily movement, and exercise. Eating below your TDEE creates a calorie deficit and leads to weight loss over time; eating above it leads to weight gain.
This calculator estimates TDEE by multiplying your BMR (basal metabolic rate) by an activity factor that matches your lifestyle. For best accuracy, use real-world weight trends over 2–4 weeks to fine-tune the number.
How is TDEE calculated?
Step 1: Estimate BMR using Mifflin-St Jeor (default), Harris-Benedict, or Katch-McArdle if you know body fat percentage. Step 2: Multiply BMR by an activity multiplier — from 1.2 (sedentary) to 1.9 (athlete). The result is your estimated maintenance calories.
- Sedentary (×1.2): desk job, little 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
- Athlete (×1.9): physical job plus daily training
What is BMR?
BMR (Basal Metabolic Rate) is the energy your body needs to maintain vital functions at complete rest — breathing, circulation, cell repair, and temperature regulation. It typically accounts for 60–75% of TDEE for sedentary individuals.
BMR varies with age, sex, height, weight, and lean body mass. More muscle generally raises BMR slightly; that is why resistance training supports long-term calorie expenditure.
How many calories should I eat to lose weight?
Most adults succeed with a deficit of 300–500 kcal/day below maintenance — roughly 0.25–0.5 kg (0.5–1 lb) per week. A mild −250 kcal deficit is gentler; −750 kcal is aggressive and harder to sustain.
Read our complete calorie deficit guide or belly fat guide for evidence-based strategies beyond the numbers.
What is a safe calorie deficit?
A safe deficit is one you can maintain for weeks without extreme hunger, poor sleep, or declining gym performance. For many people that means 10–20% below TDEE, not crash dieting below 1,200–1,500 kcal without professional guidance.
Prioritise protein (1.6–2.2 g/kg), resistance training, and adequate sleep to preserve muscle while losing fat. See our weight loss & muscle guide for a full playbook.