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Calorie Deficit Calculator

Last updated: July 11, 2026

Calculate the daily calorie deficit needed to reach your goal weight safely. Determine your TDEE, required daily intake, estimated fat loss per week, and projected completion date.

How to Use This Calorie Deficit Calculator

  1. Select your Gender (Male or Female) using the toggle buttons.
  2. Enter your Age in years.
  3. Enter your Height and select the unit (cm or ft/in).
  4. Enter your Current Weight and Goal Weight with units.
  5. Choose your Activity Level from the dropdown.
  6. Enter the Desired Timeframe in weeks.
  7. Click Calculate to see your required daily calories, deficit, and projected completion date.

Formula

Total Deficit = (Current Weight − Goal Weight) × 7,700 kcal/kg
Daily Deficit = Total Deficit / (Timeframe × 7)
Required Calories = TDEE − Daily Deficit
Min Safe Intake: 1,200 kcal/day (women), 1,500 kcal/day (men)

TDEE is calculated using the Mifflin-St Jeor equation. 7,700 kcal approximately equals 1 kg of body fat. The minimum safe intake ensures you receive adequate nutrition.

Examples

Example 1: Moderate Deficit

Male, 30 years, 80 kg, 175 cm, goal 70 kg in 12 weeks, moderate activity:
TDEE = 2,624 kcal. Deficit = 10 kg × 7,700 / (12 × 7) = 917 kcal/day
Required = 2,624 − 917 = 1,707 kcal/day

Example 2: Rapid Weight Loss

Female, 25 years, 70 kg, 165 cm, goal 60 kg in 8 weeks, sedentary:
TDEE = 1,670 kcal. Deficit = 10 kg × 7,700 / (8 × 7) = 1,375 kcal/day
Required = 1,670 − 1,375 = 295 kcal — below minimum, extend timeframe!

Example 3: Slow and Steady

Male, 40 years, 90 kg, 180 cm, goal 85 kg in 20 weeks, active:
TDEE = 3,243 kcal. Deficit = 5 kg × 7,700 / (20 × 7) = 275 kcal/day
Required = 3,243 − 275 = 2,968 kcal/day

Frequently Asked Questions

How many calories should I eat to lose weight?

Subtract a calorie deficit from your TDEE (Total Daily Energy Expenditure). A 500-calorie deficit yields about 0.5 kg (1 lb) of weight loss per week. Never eat below 1,200 kcal/day for women or 1,500 kcal/day for men without medical supervision.

Is a 500 calorie deficit safe?

Yes, a 500-calorie deficit is widely considered safe and sustainable. It leads to approximately 0.5 kg (1 lb) of weight loss per week, which is within the recommended rate of 0.5–1 kg per week by most health organizations.

How fast can I lose weight safely?

Most health experts recommend losing 0.5–1 kg (1–2 lbs) per week. Faster weight loss is possible with larger deficits but may lead to muscle loss, nutrient deficiencies, gallstones, and metabolic slowdown. Consult a healthcare professional for personalized guidance.

What is a calorie deficit?

A calorie deficit occurs when you consume fewer calories than your body burns. Your body then uses stored energy (fat and sometimes muscle) to make up the difference, resulting in weight loss over time.

Disclaimer: This calorie deficit calculator provides estimates for informational purposes only. Individual results vary based on genetics, metabolism, medical conditions, and other factors. Consult a healthcare professional or registered dietitian before making significant changes to your diet.

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