Calorie deficit calculator

A calorie deficit means eating fewer calories than your body burns in a day. It is the underlying mechanism of all fat loss — when intake is below expenditure, the body makes up the difference from stored energy, including body fat. Paired with resistance training and adequate protein, that lost weight comes predominantly from fat.

For most men, 250 to 500 calories below maintenance per day — a mild to standard deficit — is the sustainable range. A 750-calorie aggressive deficit can be used for short stretches, especially at higher body fat, but it is harder to sustain and risks muscle loss. Never sit below your BMR for sustained periods.

Roughly one pound of fat per 3,500-calorie cumulative deficit. So a 500-calorie daily deficit projects to about 1 pound per week, 250 per day to about 0.5 pound, and 750 per day to about 1.5 pounds. These are estimates — actual loss varies, so adjust based on a 2-3 week weight trend.

Faster on the scale, but not better. Too aggressive a deficit strips muscle along with fat, tanks training performance, and is very hard to sustain — which usually ends in regain. A moderate deficit you can hold for months reaches a better, more lasting result than a steep one you quit. Steady is the genuinely fast route.

Usually the deficit is smaller than you think — untracked calories from oils, drinks, bites, and weekend meals quietly close the gap. It can also be normal 1-2 week fluctuation from water and food volume. Track intake honestly, judge by a 2-3 week weight trend rather than day to day, and recalibrate if the trend is flat.