Calorie Calculator

This calculator starts from your maintenance calories — Mifflin-St Jeor BMR multiplied by a Harris-Benedict activity factor — then adjusts for your goal. Losing about 0.25 kg per week needs roughly a 275 kcal daily deficit and 0.5 kg per week about 550 kcal, based on the approximation that 1 kg of body fat stores about 7,700 kcal.

Targets are never set below widely used safety floors of 1,200 kcal/day for women and 1,500 kcal/day for men; if your goal would go lower, the result is clamped and flagged. These are general educational estimates, not medical advice — very low intakes belong under professional supervision.

The formula

Target = TDEE + goal adjustment (−550 / −275 / 0 / +275 / +550 kcal), minimum 1,200 (women) / 1,500 (men)

Worked example

Maintenance of 2,759 kcal minus 550 gives a target of 2,209 kcal per day for losing about 0.5 kg per week.

The example is pre-loaded in the result panel — press Calculate with your own numbers to replace it.

Frequently asked questions

Why is there a minimum calorie floor?

Below about 1,200 kcal (women) or 1,500 kcal (men) it becomes very hard to cover essential nutrients, and muscle loss and side effects rise. The calculator clamps targets at those floors and tells you when it does.

How fast should I expect to lose weight?

The 7,700 kcal-per-kg rule is a rough average — early weeks include water shifts, and the body adapts over time. Judge progress by the 3–4 week trend, not single weigh-ins.

Should I eat back exercise calories?

Your activity multiplier already includes typical exercise. Adding gym calories on top usually double-counts them and stalls fat loss.

Category: Health & Fitness calculators

BMR	1,780 kcal/day
Maintenance (TDEE)	2,759 kcal/day
Target calories	2,209 kcal/day
Note	Target = maintenance calories (TDEE) plus your goal adjustment.