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Protein Calculator

Find your daily protein target in grams based on body weight, activity, and goal — from minimum health needs to higher intakes for training and muscle gain.

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Enter your weight and goals, then tap Calculate.

This tool provides general informational estimates only and is not medical advice, diagnosis, or treatment. Results use population-average formulas and may not fit your individual situation. Always consult a qualified healthcare professional before making health, diet, or medical decisions.

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How much protein do you need?

Protein supports muscle repair, immune function, hormones, and satiety. Needs vary by weight, age, activity, and goal.

General guidelines (g per kg body weight)

Minimum (RDA): ~0.8 g/kg — baseline for sedentary adults.
Active / general fitness: ~1.2–1.6 g/kg.
Fat loss (preserve muscle): ~1.6–2.0 g/kg.
Muscle gain / heavy training: ~1.6–2.2 g/kg.

Turn protein grams into a full meal plan with our macro calculator or track automatically in the SmartEat app.

Frequently asked questions

How much protein should I eat per day?

Most healthy adults need at least 0.8 g per kg of body weight. Active people and those losing fat or building muscle often do better with 1.2–2.0+ g per kg.

Can you eat too much protein?

For healthy kidneys, moderately high protein intakes are generally well tolerated. People with kidney disease should follow medical guidance. Very high intakes may displace other nutrients.

Do I need protein supplements?

Not necessarily. Whole foods (eggs, fish, poultry, dairy, legumes, tofu) can cover your needs. Supplements are optional for convenience when whole-food intake is hard to hit.

Sources & methodology

Formulas and reference ranges used by this calculator come from peer-reviewed and official public-health sources:

Institute of Medicine — Recommended Dietary Allowance (RDA) for protein: 0.8 g/kg/day for most adults.
International Society of Sports Nutrition — protein recommendations for physically active people: roughly 1.4–2.0 g/kg/day depending on goal and training load.
Academy of Nutrition and Dietetics — protein needs vary with age, activity, and health status; individualized plans are best.

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