Protein Calculator
Use this free Protein Calculator to calculate your Protein needs instantly and accurately.
About you
Protein target
What is a Protein Calculator?
A Protein Calculator estimates your daily protein needs based on your body weight and activity level. Getting enough protein is essential for muscle repair, immune function, and overall health.
How to calculate protein intake manually (the formula)
Daily protein (g) = body weight (kg) × protein factor. Sedentary: 0.8 g/kg. Light activity: 1.2 g/kg. Active: 1.6 g/kg. Building muscle: 2.0 g/kg. A 72 kg active person needs 72 × 1.6 = 115 g of protein daily.
Example calculation
A 65 kg woman who exercises 3–4 times per week (active, 1.6 g/kg): 65 × 1.6 = 104 g of protein per day. That is roughly 26 g per meal across 4 meals.
Common mistakes
- Using total body weight when overweight — For obese individuals, using lean body mass or adjusted body weight gives a more accurate protein target.
- Spreading protein too thinly — Your body uses protein more effectively when you consume 20–40 g per meal rather than one large serving.
- Ignoring protein quality — Animal proteins are complete (all essential amino acids). Plant-based diets need a variety of sources to cover all amino acids.
Frequently asked questions
How much protein do I need per day?
Protein needs vary by activity level. Sedentary adults need about 0.8 g per kg of body weight, active people need 1.2 to 1.6 g/kg, and those building muscle need up to 2.0 g/kg.
How is protein intake calculated?
Protein intake is calculated by multiplying your body weight in kilograms by a protein factor based on your activity level. For example, 72 kg at 1.2 g/kg = 86 g of protein per day.
Can I eat too much protein?
Very high protein intake (over 2.5 g per kg of body weight) may stress the kidneys over time. Stick to recommended ranges and consult a doctor if you have kidney concerns.
What are good sources of protein?
Good protein sources include lean meat, poultry, fish, eggs, dairy, legumes, tofu, and protein supplements. Aim for a variety of sources for complete amino acid profiles.
Do I need more protein as I age?
Yes, older adults may benefit from higher protein intake (1.2 to 1.5 g/kg) to counteract age-related muscle loss and maintain strength.