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Calorie Calculator

Calculate your daily calorie needs for weight loss, maintenance, or gain. Includes macronutrient breakdown.

yrs
kg
cm

Health information disclaimer: This calculator provides general estimates for informational purposes only and is not medical or nutritional advice. Individual calorie needs vary. Consult a qualified healthcare professional or registered dietitian for personalized guidance.

How It Works

We use the Mifflin-St Jeor equation to calculate your BMR (Basal Metabolic Rate), then multiply by your activity level to get your TDEE (Total Daily Energy Expenditure). We also provide a macronutrient breakdown based on a balanced diet (30% protein, 40% carbs, 30% fat).

BMR & TDEE Explained

BMR (Basal Metabolic Rate) is the energy your body uses just to stay alive at rest — breathing, circulating blood, keeping cells functioning. TDEE (Total Daily Energy Expenditure) is BMR multiplied by an activity factor, representing the calories you burn in a typical day including movement.

Men: BMR = 10×kg + 6.25×cm − 5×age + 5

Women: BMR = 10×kg + 6.25×cm − 5×age − 161

TDEE = BMR × Activity Factor

Activity factors: Sedentary 1.2, Light 1.375, Moderate 1.55, Active 1.725, Very Active 1.9. Weight loss/gain targets subtract/add 500 calories (≈1 lb/week).

Example

A 30-year-old male, 75 kg, 180 cm, moderately active: BMR = 1,725 kcal, TDEE = 2,674 kcal/day. To lose weight: 2,174 kcal/day.

Assumptions & Limitations

  • Mifflin-St Jeor is an estimate: It's one of the most accurate formulas, but real BMR varies by body composition, genetics, and hormones. Individual variation can be ±200 calories.
  • Activity levels are self-reported: Most people overestimate their activity. If unsure, start with Sedentary and adjust based on results.
  • The 500-calorie rule is a rough guide: As you lose weight, your TDEE drops, so the same deficit produces less loss over time. Weight loss is not linear.
  • Not for eating disorders, pregnancy, or athletes: These groups need individualized guidance from a professional.
  • Macro split is a default, not a prescription: The 30/40/30 split suits general goals. Athletes, low-carb dieters, or those with medical conditions may need different ratios.

Frequently Asked Questions

How many calories do I need per day?

Most women need 1,800-2,400 calories, most men need 2,200-3,000 calories daily, depending on age, weight, height, and activity level.

How do I calculate my BMR?

BMR (Basal Metabolic Rate) is calculated using the Mifflin-St Jeor equation: Men: 10×weight(kg) + 6.25×height(cm) - 5×age + 5. Women: 10×weight(kg) + 6.25×height(cm) - 5×age - 161.

How many calories to lose weight?

To lose 1 pound per week, create a 500 calorie daily deficit (eat 500 fewer calories than your TDEE). This results in about 1-2 pounds of weight loss per week.

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