Calorie Deficit Calculator
The daily deficit behind a weight goal and a date, and whether that pace is wise.
The arithmetic of weight loss
A kilogram of body fat stores roughly 7,700 kcal (a pound about 3,500). Divide the total energy by your timeframe and that is the daily deficit: 5 kg in 12 weeks needs about 460 kcal per day. Subtract the deficit from your maintenance calories (TDEE) to get the daily eating target.
Pick the pace, not just the goal
0.5 to 1% of body weight per week is the range that preserves muscle and stays livable; for most people that is 0.3 to 0.8 kg. Halving the timeframe doubles the daily deficit, and deficits beyond 1,000 kcal/day rarely survive contact with real life. The math is exact; appetite is not.
Why the loss slows down
As weight drops, maintenance calories drop too, so a fixed eating target buys a shrinking deficit. Water weight also exaggerates the first weeks and masks the later ones. Recalculate your TDEE every 5 kg, expect the scale to move in steps rather than a line, and judge progress on 2 to 3 week averages.