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Protein Calculator for Weight Loss

Calculate how much protein you need to preserve muscle while losing fat. Higher protein during a calorie deficit keeps you full and protects lean mass.

Why Protein Matters for Weight Loss

Preserves Muscle

During a calorie deficit, your body can break down muscle for energy. Higher protein intake (1.2–2.0 g/kg) signals your body to preserve lean tissue and prioritize fat loss instead.

Increases Satiety

Protein is the most satiating macronutrient. Eating more protein helps you feel full longer, reducing cravings and making it easier to stick to your calorie deficit.

Boosts Metabolism

Protein has the highest thermic effect of food — your body burns 20–30% of protein calories just digesting it, compared to 5–10% for carbs and 0–3% for fats.

Protein Intake During a Calorie Deficit

When eating fewer calories than you burn, your protein needs actually increase compared to maintenance. Research supports 1.2–2.0 g per kg of body weight per day during a deficit, with the higher end (1.6–2.0 g/kg) being especially beneficial if you are also resistance training.

Combining higher protein with resistance training during a calorie deficit is the most effective strategy for losing fat while maintaining (or even gaining) muscle mass — a process sometimes called body recomposition.

Frequently Asked Questions

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Disclaimer: This calculator provides estimates based on published research. Individual results vary. Consult a registered dietitian or healthcare provider for personalized guidance, especially if you have health conditions.