Calorie Deficit Calculator
Want to lose weight steadily without guessing? Enter your details to find your maintenance calories, then pick a safe weekly loss target to get the daily calorie number that keeps you in a steady deficit.
How to use
- Enter your sex, age, weight and height.
- Choose your activity level.
- Choose a weekly loss target and read your daily calorie target.
Note
Maintenance uses the Mifflin-St Jeor formula. The deficit uses the approximation that 1 kg of body fat stores about 7,700 kcal. Very low calorie targets are flagged because intakes below about 1,200 kcal (women) or 1,500 kcal (men) are hard to keep nutritionally adequate without supervision. Estimate only — not medical advice.
Frequently Asked Questions (FAQ)
How is the daily target calculated?
Maintenance calories are estimated with the Mifflin-St Jeor formula, then a deficit is subtracted using the approximation that 1 kg of body fat stores about 7,700 kcal.
What weekly loss targets can I pick?
0.25, 0.5, 0.75, or 1 kg per week. A slower target is easier to sustain.
Why is 7,700 kcal used for 1 kg of fat?
It is the standard energy approximation for body fat, so dividing it by 7 gives the daily deficit needed to lose that weight in a week.
What if my calorie target is very low?
Intakes below about 1,200 kcal for women or 1,500 kcal for men are flagged, because a slower loss rate is usually safer and easier to sustain.