Weight Loss Calculator

Take your TDEE and subtract 250 to 500 calories. That produces roughly 0.25 to 0.5 kg (0.5 to 1 lb) of loss per week, which is the range most clinical guidance considers sustainable. The calculator does this for you and refuses to drop below 1,200 calories for women or 1,500 for men, the floors below which meeting micronutrient needs becomes difficult.

At a moderate 0.5 kg per week, about 20 weeks, or roughly five months. At an aggressive 1 kg per week it would be 10 weeks, but sustaining a 1,100 calorie daily deficit that long is difficult and costs more lean mass. Most people do better treating the faster number as a best case and planning against the moderate one.

Only for people carrying substantial excess weight. The usual guidance is to stay under 1% of body weight per week: at 100 kg that permits 1 kg, at 65 kg it means 0.65 kg. Above that threshold, a growing share of what you lose is muscle and water rather than fat, and the deficit required is large enough to be hard to hold.

They assume 7,700 calories per kilogram of fat and a fixed metabolic rate, and the second assumption breaks down. As you get lighter, your BMR falls because there is less tissue to maintain, and your body burns fewer calories doing the same activities. Real loss curves flatten while a linear projection keeps its slope. Recalculate every four to six weeks with your current weight.

Both, weighted toward eating for the bulk of it. Diet changes generate a larger deficit for less effort: skipping a 400 calorie snack takes no time, while burning 400 calories takes about 90 minutes of brisk walking. But adding activity preserves lean mass during a deficit and stops your TDEE from falling as fast, so a deficit built entirely from food restriction tends to stall sooner.

Most commonly your TDEE has fallen: you are lighter, so the same deficit no longer exists. It can also be water retention masking real fat loss, which is normal after a hard workout or a high-sodium day and can hide two weeks of progress. Recalculate at your current weight, and judge progress on a two-to-three week trend rather than day-to-day readings.

There is no fixed number, because it depends on the size of your deficit and your weight. As a rough guide, 10,000 steps burns roughly 300 to 500 calories for most adults, which is about half a typical daily deficit. Walking is the easiest activity to sustain at that volume, which is why it holds up better than more intense options over the months a real goal takes.