Calorie Deficit Calculator

Estimate how long it will take to reach your target weight with a chosen daily calorie deficit.

What is the Calorie Deficit Calculator?

A calorie deficit means eating less energy than you burn, so the body uses stored fat.

How does it work?

About 7,700 kcal corresponds to 1 kg of body fat. The total deficit is divided by your daily deficit to estimate days.

Formula

Days = (current − target kg) × 7,700 ÷ daily deficit

Example

Losing 8 kg needs a total deficit of 61,600 kcal. At 500 kcal a day that takes about 124 days (roughly 18 weeks).

Frequently asked questions

Why does weight loss slow down over time?

As you lose weight, your TDEE falls, so the same intake creates a smaller deficit. Recalculate every few kilograms.

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