Weight Loss Calculator
Get your daily calorie target, weekly deficit, and projected goal date based on your body and activity — free and instant.
This calculator is for informational purposes only — not medical advice. Very low calorie intakes can be unsafe; consult a healthcare professional before starting a weight loss plan, especially with a medical condition.
How your plan is calculated
The plan is built from three well-established nutrition formulas:
- BMR (Mifflin-St Jeor) — your resting calorie burn:
Men: 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
Women: 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161 - TDEE — BMR multiplied by your activity factor (1.2–1.9), estimating total daily burn.
- Calorie deficit — about 7,700 kcal per kilogram of body fat. Your daily deficit is (weekly rate × 7,700) ÷ 7, and your daily calorie target is TDEE minus that deficit.
- Goal date — (current weight − target weight) ÷ weekly rate, counted forward in weeks from today.
Example: at 0.5 kg per week you need a daily deficit of about 550 kcal. Real-world loss varies with water retention, muscle gain, and tracking accuracy — treat the goal date as a guide, not a guarantee.
Frequently asked questions
How many calories should I eat to lose weight?
Eat below your TDEE (total daily energy expenditure) by a steady deficit. This calculator estimates your TDEE from your body and activity, then subtracts the deficit matching your chosen weekly loss rate to give a daily calorie target.
Is losing 1 kg per week safe?
Up to about 1 kg per week is generally considered the upper end of a safe, sustainable rate for most adults. Slower rates like 0.25–0.5 kg per week are easier to maintain long term. Consult a professional before pursuing aggressive deficits.
What is the Mifflin-St Jeor equation?
It is the most widely validated formula for estimating resting calorie burn (BMR) in healthy adults: 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5 for men, or − 161 for women. Dietitians use it as the standard starting point.
What should I do if my weight plateaus?
Plateaus are normal. Recalculate your TDEE at your new weight, check that you are tracking food accurately, stay consistent with activity and sleep, and give it 2–3 weeks before adjusting your target.