Protein Calculator
Find out how many grams of protein you need per day based on your weight, activity level and goal — with science-based ranges.
TL;DR
Sedentary: 0.8–1.2 g/kg · Active: 1.2–1.6 g/kg · Fat loss: 1.6–2.2 g/kg · Muscle gain: 1.6–2.0 g/kg. Enter your weight and your range appears instantly. Everything runs in your browser — nothing is stored.
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What decides your protein needs?
Official guidelines (RDA) say 0.8 g per kg per day — but that's the minimum to avoid deficiency, not the optimum for anyone who trains. The International Society of Sports Nutrition (ISSN) and recent meta-analyses support 1.4–2.2 g/kg for active people. Three things set your number: body weight, activity level and goal.
Science-based ranges by goal
- Sedentary: 0.8–1.2 g/kg — enough for basic tissue repair.
- Regular training (maintenance): 1.2–1.6 g/kg — recovery and muscle preservation.
- Fat loss: 1.6–2.2 g/kg — the single strongest tool for keeping muscle in a calorie deficit. We cover why in the calorie deficit guide.
- Muscle gain: 1.6–2.0 g/kg — there's no strong evidence that going beyond this adds benefit.
Worked example: 70 kg, active, cutting
70 × 1.6 = 112 g (lower bound) · 70 × 2.2 = 154 g (upper bound)
A practical target: ~130 g per day, split across 4 meals (~32 g each). For reference, a chicken breast (150 g) has ≈ 46 g of protein, a bowl of Greek yogurt ≈ 10 g, two eggs ≈ 12 g.
Where to get your protein
- Animal sources: chicken, turkey, fish, eggs, dairy, lean beef — complete amino acid profiles.
- Plant sources: lentils, chickpeas, beans, tofu, oats — mix sources to cover all essential amino acids.
- Supplements: if food alone doesn't get you there, protein powder is a practical tool. See our protein powder guide.
Signs you're not eating enough protein
Constant hunger, slow recovery, weak hair and nails, and losing muscle despite training are the most common signs — the full list is in protein deficiency signs. To see your whole nutrition picture, try the macro calculator.
Not medical advice. If you have kidney disease, plan your protein intake with your doctor.
Frequently asked questions
How much protein should I eat per day?
A sedentary adult needs 0.8–1.2 g per kg of body weight. Regular training: 1.2–1.6 g/kg. Fat loss while keeping muscle: 1.6–2.2 g/kg. Muscle gain: 1.6–2.0 g/kg.
Why do I need more protein when losing weight?
In a calorie deficit your body can break down muscle for energy. Higher protein plus resistance training largely prevents that. Protein is also the most filling macronutrient, which makes the deficit easier to stick to.
Is too much protein harmful?
For people with healthy kidneys, there's no strong evidence of harm up to 2.2 g/kg. Anyone with kidney disease should consult a doctor. Very high intakes also show no extra benefit.
When should I eat my protein?
Total daily amount matters most. Spreading it across 3–5 meals with 25–40 g each stimulates muscle protein synthesis better than one huge meal. A protein-rich meal within a few hours after training is a good rule.
Related tools
Hitting your protein target is easier with tracking
KeplerFit counts your protein from a photo of your meal, shows what's missing at the end of the day, and coaches your weekly protein average.
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