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Calorie deficit calculator

A kilogram of body fat is roughly 7,700 kcal. Losing half a kilo a week means a deficit near 550 kcal a day.

SexAgeyearsHeightcmWeightkgActivity

2,091

kcal / day

For roughly 0.5 kg a week. Maintenance is 2,641 kcal.

Slower and steadier: 2,366 kcal for about 0.25 kg a week.

Deficits beyond about 25% of maintenance tend to cost muscle and adherence.

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Mifflin-St Jeor for maintenance; the 7,700 kcal/kg figure is a long-standing approximation, not a precise constant.

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