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Find your ideal daily protein intake in grams based on your body weight, activity level and fitness goal.
The Protein Calculator above turns your body weight, activity level, and goal into a daily protein target in grams. Here is how to use it:
Tip: Recalculate whenever your weight changes by more than 5 kg or your training changes substantially. Protein needs scale with body weight, so a target set at 90 kg is wrong at 75 kg.
Protein is the macronutrient your body uses to build and repair tissue — muscle, skin, enzymes, hormones, and immune cells are all made from amino acids, protein’s building blocks. Nine amino acids are essential, meaning your body cannot make them and you must eat them. Unlike fat or carbohydrate, the body keeps no meaningful protein reserve, so a steady daily supply matters.
The official RDA (Recommended Dietary Allowance) is 0.8 grams per kilogram of body weight per day — the minimum to avoid deficiency in sedentary adults. But the RDA is a floor, not a target. Research on active people consistently finds better outcomes — more muscle retention, better recovery, greater satiety — at 1.6–2.2 g/kg, roughly double to triple the RDA. The gap between “enough to survive” and “enough to thrive” is where this calculator operates.
Why does activity raise the requirement? Exercise damages muscle fibers (especially resistance training) and increases muscle protein breakdown; dietary protein supplies the amino acids for muscle protein synthesis (MPS), the repair process that makes you stronger. Endurance training also raises needs through tissue turnover and the use of amino acids as auxiliary fuel. In a calorie deficit, protein becomes even more critical: with energy scarce, the body is tempted to burn muscle, and high protein intake (1.8–2.2 g/kg) is the main dietary defense.
Protein also helps through satiety and the thermic effect of food: it is the most filling macronutrient, and digesting it burns roughly 20–30% of its calories (versus 5–10% for carbs and 0–3% for fat). That is one reason high-protein diets consistently outperform in weight-loss trials — people spontaneously eat less.
Quality matters too. Complete proteins (meat, fish, eggs, dairy, soy) contain all essential amino acids; most plant proteins are incomplete but combine well (rice + beans, hummus + pita). Leucine, one essential amino acid, acts as the trigger for muscle protein synthesis — about 2.5–3 g per meal (found in ~30 g of whey or ~150 g of chicken breast) maximally stimulates the process.
The calculator uses a simple, evidence-based formula:
Daily protein (g) = body weight (kg) × protein factor
Protein calories = grams × 4 (protein provides 4 kcal per gram)
The protein factor ranges from the 0.8 g/kg RDA floor to 2.2 g/kg for hard-training athletes, selected from your activity level and goal: roughly 1.2 for sedentary, 1.6 for moderately active, 1.8–2.0 for very active, and up to 2.2 for athletes or aggressive fat loss.
Worked example 1: A 70 kg sedentary adult. Using the RDA floor: 70 × 0.8 = 56 g/day, which is 56 × 4 = 224 kcal from protein. Using the more practical sedentary factor of 1.2: 70 × 1.2 = 84 g/day = 336 kcal. The 56 g figure prevents deficiency; the 84 g figure better supports an aging adult’s muscle maintenance.
Worked example 2: An 80 kg recreational athlete training 5 days a week. At a factor of 2.0: 80 × 2.0 = 160 g/day = 640 kcal from protein. Spread across 4 meals, that is 40 g per meal — for instance, 150 g of chicken breast (≈47 g protein) at lunch, Greek yogurt and eggs at breakfast, and so on. In ounces: 160 ÷ 28.35 ≈ 5.6 oz of pure protein daily.
Notice the range: the same 70–80 kg body needs anywhere from 56 g to 187 g depending on lifestyle — a 3× spread. That is why generic “eat 100 g” advice fails, and why the factor must match the person.
Consider an 85 kg strength athlete training 6 days a week with a goal of building muscle. At a factor of 2.2 g/kg: 85 × 2.2 = 187 g/day, equal to 187 × 4 = 748 kcal from protein — roughly 25% of a 3,000 kcal bulking diet.
Distribution matters as much as the total. Muscle protein synthesis responds best to 3–5 protein feedings of 30–50 g spread through the day, each delivering 2.5–3 g of leucine. For 187 g, a practical split: breakfast 40 g (Greek yogurt + eggs), lunch 50 g (200 g chicken breast), post-workout 40 g (whey shake + milk), dinner 57 g (250 g salmon or beef + sides). Each feeding maximally triggers MPS, and the day’s total supplies the raw material.
During a dedicated muscle-gain phase, protein slightly above 2.0 g/kg shows diminishing returns — extra calories from carbs then help more by fueling training. But dropping below 1.6 g/kg while training hard measurably slows muscle gain in studies. The athlete’s edge is consistency: hitting 187 g daily for months, not perfectly for a week.
Now a 90 kg person losing fat on a moderate calorie deficit. Protein needs rise in a deficit to defend muscle: at 2.0 g/kg, 90 × 2.0 = 180 g/day = 720 kcal from protein. On an 2,200 kcal cutting diet, that is about 33% of calories — high, but exactly what preserves lean mass while fat comes off.
The math of the deficit shows why: a 500 kcal daily deficit over 12 weeks should remove about 5.5 kg of fat (500 × 84 days ÷ 7,700 kcal per kg of fat ≈ 5.5 kg). Without high protein and resistance training, up to 25–30% of lost weight can be muscle — roughly 1.5 kg of metabolically precious tissue. With 180 g of protein daily plus lifting, muscle loss typically drops below 10% of total weight lost.
Satiety is the second payoff. At 180 g/day spread over 3–4 meals (45–60 g each), hunger in a deficit is dramatically lower than on a low-protein cut — protein’s thermic effect also burns an extra ~100–150 kcal daily just in digestion. Practical anchors: a palm-and-a-half of meat or fish per meal, plus a protein-rich snack, gets most people to 180 g without powders.
Complete your nutrition picture with these tools:
This page hosts a free Protein Calculator estimating daily protein needs. Inputs: body weight (kg), activity level (sedentary, moderately active, very active, athlete), goal (lose fat, maintain, build muscle). Outputs: daily protein target (g/day), ounces of protein, calories from protein (grams × 4), and the g/kg factor used. Formula: daily protein (g) = body weight (kg) × protein factor; factors range from the 0.8 g/kg RDA floor to 2.2 g/kg for athletes. Example: 70 kg, very active, maintain → 140 g/day (4.9 oz, ~560 kcal, 2.00 g/kg). The page also covers protein distribution across meals (30–50 g per feeding), protein in fat loss (1.8–2.2 g/kg preserves muscle), and common mistakes such as using total weight at high body fat.
Enter your body weight and pick your activity level. The calculator multiplies your weight in kilograms by a science-backed factor (1.2–2.2 g/kg) matched to how active you are.
Formula: Daily protein (g) = body weight (kg) × protein factor; protein calories = grams × 4.
Sedentary adults need about 1.2 g/kg; active people 1.6–2.0 g/kg; athletes up to 2.2 g/kg. A 70 kg very active person needs about 140 g daily.
Intakes up to 2.2 g/kg are well tolerated by healthy people.
Total daily intake matters most; spreading across 3–4 meals of 30–50 g each works well.
Not necessarily — meat, dairy, eggs, legumes and soy can cover 140 g/day.
Yes — protein is the most satiating macronutrient and preserves muscle in a deficit. Aim for 1.8–2.2 g/kg while cutting.
It depends on activity: 56 g/day meets the 0.8 g/kg RDA minimum, 84 g/day (1.2 g/kg) suits a sedentary adult, and 112–140 g/day (1.6–2.0 g/kg) is better for active people. The calculator above picks the right factor for your lifestyle.
For a 90 kg athlete at 2.2 g/kg, 198 g/day is appropriate. For a 60 kg sedentary person, 200 g would be excessive and mostly wasted. Match intake to body weight and training — healthy kidneys handle up to 2.2 g/kg without issue.
Yes. Muscle protein synthesis stays elevated for 24–48 hours after training, and muscle is built on rest days. Keep your daily protein consistent rather than cycling it with workouts.
Sources: National Academies RDA for protein (0.8 g/kg/day); International Society of Sports Nutrition (ISSN) position stand on protein intake; Academy of Nutrition and Dietetics sports nutrition guidance.
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