Calorie deficit calculator (for weight loss)
Find out how many calories to eat per day to lose (or gain) weight at the pace you choose.
Based on ~7700 kcal per kilo. Losing more than ~0.5–1 kg per week tends to cost muscle and isn't sustainable. Not medical advice.
How the calculation works
Losing (or gaining) weight is fundamentally an energy equation: you lose weight when you spend more calories than you eat — a calorie deficit. Gaining is the opposite (a surplus).
The classic reference is that each kilo of body fat stores about 7,700 kcal. From your desired weekly pace:
daily deficit = (kg per week × 7,700) ÷ 7
target calories = maintenance (TDEE) − deficit
Step-by-step example (lose 0.5 kg/week, TDEE 2,200)
- Weekly deficit: 0.5 × 7,700 = 3,850 kcal
- Daily deficit: 3,850 ÷ 7 = 550 kcal/day
- Target: 2,200 − 550 = 1,650 kcal/day
What pace is safe
Losing 0.5–1 kg per week is generally considered sustainable. Overly aggressive deficits cost muscle and are hard to keep.
Why the scale isn't linear
The body adapts and scale weight fluctuates with water and salt. The 7,700 kcal rule is a useful average, not an exact promise — watch the multi-week trend.
Examples
- Lose 0.5 kg/wk with TDEE 2,200: target ≈ 1,650 kcal/day.
- Gain 0.25 kg/wk with TDEE 2,500: target ≈ 2,775 kcal/day (surplus).
Frequently asked questions
How do I find my maintenance calories?
Use the BMR and daily calories (TDEE) calculator, which estimates it from your weight, height, age and activity.
Can I speed it up by cutting a lot?
Not advisable. Very large deficits cost muscle, cause fatigue and yo-yo. 0.5–1 kg/week is sustainable.
Is the deficit enough, or must I train?
The deficit controls weight; training (especially strength) preserves muscle. Together they work best.
Why did I stop losing weight eating the same?
Because your burn fell along with your weight. A smaller body needs less, so the same intake that created a deficit becomes maintenance. Recalculate your target every 4–5 kg lost.
How much protein during a deficit?
The commonly cited range for people in a deficit who train is 1.6 to 2.2 g per kilo of body weight per day, alongside strength training.
Can I lose weight with exercise alone?
It is much harder than it looks. For someone training 4× a week, exercise accounts for roughly 7% of daily burn, while resting metabolism is about 65%.
Is there a minimum calorie floor?
As a practical reference, diets below ~1,200 kcal/day for women and ~1,500 kcal/day for men make it hard to meet micronutrient needs and usually require supervision.
Sources and references
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Updated on June 30, 2026 · by Rafael Rossi · Methodology & sources