Weight Loss Calculator
This calculator provides estimates for educational purposes only and is not medical advice. Actual weight loss varies based on individual metabolism, adherence, and other factors. Consult a healthcare provider before starting any weight loss plan.
How this calculator works
We calculate your Total Daily Energy Expenditure (TDEE) using the Harris-Benedict equation, then simulate weight loss week by week. As your weight decreases, your TDEE drops — so we recalculate it at each step rather than assuming a constant rate. This gives you a more realistic timeline than simple linear estimates.
Understanding calorie deficits
One kilogram of body fat contains approximately 7,700 calories. To lose 0.5 kg per week, you need a daily deficit of about 550 calories. We show three deficit levels so you can choose the pace that fits your lifestyle:
- Mild (250 cal/day): Slow but very sustainable, minimal hunger
- Moderate (500 cal/day): The "gold standard" — noticeable progress without suffering
- Aggressive (750 cal/day): Faster results, but harder to maintain and may affect energy
Why weight loss slows down
As you get lighter, your body burns fewer calories at rest. The same 500-calorie deficit that worked at 90 kg produces slower loss at 75 kg because your TDEE has dropped. This is normal — not a plateau. Our calculator models this adaptive effect to give you realistic dates.
Ready to start? Calculate your exact calorie target or find your ideal macro split. New to calorie counting? Read our beginner's guide.