The maths
One kilogram of body fat stores about 7,700 kcal. Divide that by your weeks and days to get the daily deficit — the gap between calories eaten and calories burned.
A safe pace
Most health authorities suggest around 0.5–1 kg (1–2 lb) per week. Faster plans usually mean muscle loss and rebound. If the tool flags your pace as fast, consider adding more weeks.
Deficit, not starvation
The deficit can come from eating a little less, moving a little more, or both. Very low-calorie diets need medical supervision.
Frequently Asked Questions
How fast should I aim to lose weight?
About 0.5–1 kg per week is the widely advised sustainable range.
What is a calorie deficit?
Burning more calories than you eat. A daily deficit of ~500 kcal typically loses about 0.5 kg per week.
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