Calculate how long it will take to reach your goal weight with a calorie deficit.
A weight loss calculator estimates how long it will take to reach your goal weight and how many calories you need to eat daily to achieve it. By analyzing your current weight, goal weight, height, age, and activity level, our calculator creates a personalized calorie deficit plan to help you lose weight safely and sustainably.
Weight loss occurs when you consistently consume fewer calories than you burn — creating a calorie deficit. One kilogram of body fat contains approximately 7,700 calories. Therefore, a daily deficit of 500 calories results in losing about 0.5 kg per week. A 1,000 calorie daily deficit leads to approximately 1 kg per week. Going beyond this often results in muscle loss, not just fat loss.
Most health organizations recommend losing no more than 0.5-1 kg per week for sustainable fat loss. Faster weight loss typically involves muscle loss, water weight, and metabolic slowdown — leading to the dreaded rebound effect. Slow and steady weight loss also helps build lasting habits. If you are significantly overweight, supervised faster weight loss may be appropriate under medical guidance.
A weight loss plateau occurs when your body adapts to lower calorie intake by reducing BMR. Strategies to break through: recalculate your TDEE based on new (lower) body weight, take a "diet break" eating at maintenance for 1-2 weeks to reset hormones, change your exercise routine to include new activities, reduce carbohydrate intake to shift to fat burning, and increase protein slightly to preserve muscle mass.
Weight loss fundamentally requires a sustained calorie deficit — consuming fewer calories than the body expends — and since one pound of body fat represents roughly 3,500 calories, a consistent daily deficit can be translated into an estimated weekly or monthly weight loss rate, though this relationship becomes somewhat less precise at larger deficits or over longer timeframes, since metabolic adaptation can occur as the body adjusts to sustained reduced calorie intake.
Moderate, sustainable calorie deficits, generally producing 0.5 to 1 pound of weekly loss, are widely recommended over more aggressive deficits, since gradual weight loss is more strongly associated with better long-term maintenance and lower risk of significant muscle loss compared to very rapid weight loss approaches, which often prove difficult to sustain and can trigger a stronger metabolic slowdown response.
Body weight naturally fluctuates day to day due to water retention, digestive contents, and hormonal factors unrelated to actual fat loss, which is why weight loss doesn't proceed in a perfectly smooth, predictable line even when calorie intake is being tracked consistently. Looking at weekly or monthly weight trends, rather than reacting to single-day fluctuations, gives a much more accurate and less discouraging picture of genuine progress toward a weight loss goal.
A deficit of 500 calories per day leads to approximately 0.5 kg of weight loss per week. A deficit of 1,000 calories leads to about 1 kg per week.
Most health experts recommend losing 0.5 to 1 kg per week. Losing more than 1.5 kg per week may indicate muscle loss, not just fat.
Exercise helps but diet is more important. You cannot outrun a bad diet. Combining calorie reduction with exercise gives the best long-term results.
Weight loss plateaus happen because your body adapts to lower calorie intake. Try adjusting your calorie target, changing exercise type, or taking a diet break.
