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Calorie Deficit Calculator

Find out how many calories to eat per day to reach your goal. Based on the Mifflin–St Jeor equation and the same limits Snapfork uses to build your plan.

Sex

Your daily target

2,220 kcal

≈ 491 kcal/day deficit vs. maintenance (2,711 kcal)

144 g

Protein

64 g

Fat

267 g

Carbs

Track these calories in Snapfork

Example for Male, 30, 175 cm, 80 kg. With JavaScript on, the result follows your input.

How the calculation works

The calculator estimates your basal metabolic rate with the Mifflin–St Jeor equation and multiplies it by your activity factor to get maintenance calories (TDEE). For weight loss it takes about 18% off — but never more than 500 kcal a day and never below your BMR or 1,200 kcal; at a BMI under 20 it doesn’t suggest a deficit at all. For muscle gain it adds 12%.

Protein is set per kilogram of body weight (1.8 g/kg when losing weight) to protect muscle; fat and carbohydrates follow the rules of the macro calculator.

What is a safe calorie deficit?

A deficit of 300–500 kcal per day typically yields 0.25–0.5 kg of fat loss per week — fast enough to see progress, slow enough to keep muscle and energy. Larger deficits increase hunger, fatigue and muscle loss, and are hard to sustain.

Recalculate after every 4–5 kg of weight change: as you get lighter, your maintenance calories drop. If you have a medical condition, consult a doctor or dietitian before changing your diet.

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