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Health2026-08-14·CalcMatrix

How Many Calories Do You Burn a Day? BMR, TDEE, and Calorie Deficit Explained

"Watch what you eat" doesn't mean starving — it means eating the right calories. Most people fail at fat loss because they don't know how many calories their body actually burns. Here's the simplest logic to build your own calorie ledger.

The Core Principle of Calorie-Based Fat Loss

Weight change follows one rule: a calorie deficit. When daily intake is less than daily burn, weight drops. The bigger the deficit, the faster the loss — but too large a deficit damages your metabolism, and the rebound is not worth it.

How BMR Is Calculated

Your body burns calories even lying still — that's basal metabolic rate (BMR), typically 60%–70% of total burn. The common Mifflin-St Jeor formula:

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

Manual math is error-prone — use the calorie calculator, enter age, sex, height, weight, and activity, and get BMR plus TDEE automatically.

Total Daily Energy Expenditure (TDEE)

Multiply BMR by an activity factor: sedentary ×1.2, light ×1.375, moderate ×1.55, high ×1.725. The result — TDEE — is the calorie level that maintains your weight.

GoalDaily intakeNotes
Fat lossTDEE − 300~500 kcal≈ 0.5–1 lb/week, safe and sustainable
Maintain≈ TDEEEat what you burn
Muscle gainTDEE + 200~300 kcalPair with strength training

Three Practical Fat-Loss Tips

  1. Don't go below BMR: intake under basal metabolic rate triggers "starvation mode" — you lose muscle, not fat
  2. Eat enough protein: protein is satiating and protects muscle — aim for 1.2–1.6g per kg of body weight
  3. Track the trend: start with BMI to know your baseline, then weigh in weekly

Common Misconceptions

Many assume "the less you eat, the faster you lose". In reality, chronically very-low calories lower your metabolism and cause faster rebound. Sustainable fat loss is a moderate deficit + strength training + adequate protein.

Open the calorie calculator now, get your BMR and TDEE, and start a science-based fat-loss journey without going hungry.

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