What is a safe calorie deficit?

A deficit of 250 to 500 calories a day below TDEE — roughly 0.25 to 0.5 kg (0.5 to 1 lb) a week — is a commonly cited sustainable range for most adults. Larger deficits lose weight faster but are harder to sustain and risk more muscle loss.

How big should a calorie deficit be?

It depends on how much you have to lose, your timeline and how sustainable a bigger deficit is for you personally. A smaller, sustained deficit is usually more effective long-term than an aggressive one that gets abandoned after a few weeks.

Why is there a minimum calorie floor?

Very low intakes — commonly cited around 1,200 kcal/day for women and 1,500 kcal/day for men as general reference points, not individualized numbers — risk inadequate nutrition, muscle loss and metabolic slowdown. Going below that range should only be done under professional supervision.

Why does my calorie target need to be recalculated over time?

As you lose weight your TDEE falls, because a lighter body burns fewer calories at rest and in motion. A fixed deficit calculated once will shrink in real terms as you progress — recalculate every few kilograms rather than holding one number for months.

Calorie Deficit Calculator

A calorie deficit — eating less than your body burns — is what produces weight loss. This calculator finds your total daily energy expenditure, then applies your chosen weekly rate to give a daily calorie target.

Calculate your calorie target

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How the target is calculated

Daily target = TDEE − (weekly rate × 7,700 ÷ 7)

TDEE comes from the Mifflin-St Jeor equation and your activity multiplier. See the TDEE calculator for that equation on its own.

A minimum-intake note

Very low calorie intakes carry real risks: inadequate nutrition, muscle loss and metabolic slowdown. Commonly cited general reference floors are around 1,200 kcal/day for women and 1,500 kcal/day for men — these are population-level starting points, not individualized medical advice. If your calculated target falls near or below that range, or you have any underlying health condition, talk to a healthcare provider or registered dietitian before proceeding.

Common questions

What is a safe calorie deficit?: A deficit of 250 to 500 calories a day below TDEE — roughly 0.25 to 0.5 kg (0.5 to 1 lb) a week — is a commonly cited sustainable range for most adults. Larger deficits lose weight faster but are harder to sustain and risk more muscle loss.
How big should a calorie deficit be?: It depends on how much you have to lose, your timeline and how sustainable a bigger deficit is for you personally. A smaller, sustained deficit is usually more effective long-term than an aggressive one that gets abandoned after a few weeks.
Why is there a minimum calorie floor?: Very low intakes — commonly cited around 1,200 kcal/day for women and 1,500 kcal/day for men as general reference points, not individualized numbers — risk inadequate nutrition, muscle loss and metabolic slowdown. Going below that range should only be done under professional supervision.
Why does my calorie target need to be recalculated over time?: As you lose weight your TDEE falls, because a lighter body burns fewer calories at rest and in motion. A fixed deficit calculated once will shrink in real terms as you progress — recalculate every few kilograms rather than holding one number for months.

Calorie Deficit Calculator

Calculate your calorie target

How the target is calculated

A minimum-intake note

Common questions

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