Calorie & TDEE Calculator

How It Works

This calculator uses the Mifflin-St Jeor equation to estimate the calories your body burns at rest, scales that by an activity multiplier for total daily expenditure, then applies your goal as a fixed calorie adjustment.

BMR · Mifflin-St Jeor

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

Activity multipliers (TDEE = BMR × factor)

The multiplier approximates everything you do outside of sleeping and basic bodily maintenance: walking, standing work, chores and training. ×1.2 is a mostly seated week, ×1.375 light exercise 1–3 days a week, ×1.55 moderate exercise 3–5 days, ×1.725 hard exercise 6–7 days, and ×1.9 physical work plus twice-daily or intense training.

Why −500 kcal ≈ −0.5 kg per week

−500 kcal per day is −3,500 kcal per week. A kilogram of body tissue stores roughly 7,700 kcal, so 3,500 ÷ 7,700 ≈ 0.45 — call it about half a kilo per week. It is a rough arithmetic approximation: real weekly rates drift with water balance, metabolic adaptation and adherence.

Macros

The target calories are split 30% protein / 40% carbohydrates / 30% fat and converted to grams with the standard Atwater factors — protein and carbs at 4 kcal/g, fat at 9 kcal/g.

Frequently Asked Questions