This calculator works out the daily calorie deficit and the daily calorie target you need to lose weight at the rate you choose, based on your maintenance calories. Weight loss comes down to energy balance: eat fewer calories than your body burns and it makes up the difference from stored fat, so you lose weight. The size of that gap, the deficit, decides how fast it happens, and the trick is choosing a rate that is meaningful but still comfortable to stick to, because an aggressive deficit is hard to maintain and can leave you hungry and low on energy. The arithmetic uses the well-known figure that about half a kilogram of body fat holds roughly 3,850 calories, so to lose half a kilo a week you need a deficit of about 550 calories a day. You enter your total daily energy expenditure, the calories you burn in a day, and your target weekly weight loss, and the calculator returns the daily deficit required and the daily calorie target to eat to achieve it. A loss of around 0.5 to 1 kilogram a week is a sustainable range for most people. If you do not know your maintenance calories, estimate them with a TDEE or BMR calculator first. This is general information, not medical or dietary advice; see a professional before big changes.
Uses about 7,700 calories per kg of fat. Aim for 0.5 to 1 kg a week to keep it sustainable. General information, not medical or dietary advice.
About 7,700 calories equals a kilogram of body fat. The daily deficit is your target weekly loss times 7,700, divided by 7 days. The daily calorie target is your maintenance calories minus that deficit. The monthly loss is the weekly loss times about 4.3 weeks.
With maintenance of 2,400 calories and a target of 0.5 kilograms a week, the daily deficit is about 550 calories, so your daily target is around 1,850 calories, for roughly 2.1 kilograms of loss a month.
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