Protein Intake Calculator

How Much Protein Do You Need Per Day?

Protein requirements vary enormously based on your goal, activity level, and body composition. The generic RDA of 0.36g per pound (0.8g per kg) of body weight is a minimum to prevent deficiency in sedentary adults — not an optimal target for anyone who exercises, wants to build muscle, or is trying to lose fat while preserving lean mass.

Our calculator sets your protein target based on the latest research. Enter your body weight, primary goal (muscle gain, fat loss, or maintenance), and activity level. The result is a personalized daily protein target in grams, along with a per-meal breakdown.

Quick targets by goal: Muscle building: 0.7–1.0g per pound of body weight. Fat loss (preserving muscle): 0.8–1.2g per pound. General health with moderate activity: 0.5–0.7g per pound. Sedentary adults (minimum): 0.36g per pound.

Why Protein Is the Priority Macronutrient

When it comes to body composition — how you look, how much muscle you carry, and how lean you are — protein is the single most important macronutrient. This isn't opinion; it's consistently supported by metabolic research.

During a calorie deficit (eating less to lose fat), your body doesn't just burn fat — it also breaks down muscle for energy. Adequate protein intake (0.8–1.2g/lb) signals the body to preserve muscle tissue, directing more of the deficit toward fat loss. Studies show that high-protein diets during a calorie deficit preserve 2–3x more muscle mass compared to lower-protein diets with the same calorie deficit.

During a calorie surplus (eating more to gain muscle), protein provides the amino acids needed to build new muscle tissue. Without sufficient protein, excess calories are stored primarily as fat rather than being used for muscle growth. The "sweet spot" for muscle building is 0.7–1.0g per pound — consuming more than this doesn't accelerate muscle growth but doesn't harm anything either.

At maintenance calories, adequate protein supports muscle preservation, immune function, enzyme production, hormone synthesis, and cellular repair. It also increases satiety (feeling full) more than carbohydrates or fat, making it easier to maintain your weight without constant hunger.

The thermic effect of food (TEF) is another protein advantage. Your body uses 20–30% of protein calories just to digest and process it, compared to 5–10% for carbohydrates and 0–3% for fat. Eating 100 calories of protein results in only 70–80 net usable calories. This metabolic advantage, while modest per meal, compounds over a high-protein diet.

Protein Targets by Goal

Muscle building (lean bulk): 0.7–1.0g per pound of body weight daily. A 180 lb person targets 126–180g/day. Research consistently shows diminishing returns above 1.0g/lb — the extra protein doesn't harm you, but it won't accelerate muscle growth beyond what 0.7–1.0g/lb achieves. Combine with progressive resistance training and a moderate calorie surplus (250–500 calories above TDEE).

Fat loss (cutting): 0.8–1.2g per pound of body weight daily. Higher protein during a deficit is critical for muscle preservation. A 170 lb person cutting weight should target 136–204g/day. The deeper the deficit, the more important protein becomes — aggressive cuts (750+ calorie deficit) warrant the higher end of this range.

General health and maintenance: 0.5–0.7g per pound. A 150 lb person targets 75–105g/day. This exceeds the RDA (which is a bare minimum) and supports muscle maintenance, immune function, and satiety without requiring meticulous tracking.

Endurance athletes: 0.5–0.8g per pound. Endurance training increases protein needs above sedentary levels, though not as much as resistance training. Protein supports muscle repair after long training sessions and prevents the gradual muscle loss that can occur with high-volume endurance training.

Older adults (50+): 0.6–0.9g per pound. Aging reduces the body's muscle protein synthesis response to protein intake (a phenomenon called "anabolic resistance"). Higher protein intake helps compensate, preserving muscle mass and strength that naturally decline with age (sarcopenia). Combined with resistance training, adequate protein is the most effective intervention for maintaining functional independence in older adults.

Protein Timing and Distribution

Total daily protein matters most. Research consistently shows that hitting your daily protein target is far more important than when you eat it. Whether you consume protein across 6 small meals or 2 large ones, the 24-hour muscle protein synthesis response is similar if total protein is matched.

That said, distribution has a modest benefit. Consuming 25–40g of protein per meal optimizes the muscle protein synthesis (MPS) response at each feeding. Eating 10g at breakfast and 90g at dinner is less effective than eating 50g at each meal, even though the daily total is identical. This is because MPS has a "leucine threshold" — approximately 2.5–3g of leucine (found in 25–30g of high-quality protein) is needed to maximally stimulate it.

Post-workout protein: The "anabolic window" — the idea that you must consume protein within 30 minutes of training — has been significantly debunked. Research shows the window is much larger: consuming protein within 2–3 hours of training is sufficient. If your pre-workout meal was 3+ hours before training, prioritize protein sooner after your workout. If you ate 1–2 hours before, the urgency is lower.

Pre-sleep protein: Consuming 30–40g of casein protein (slow-digesting, found in cottage cheese, casein powder, or Greek yogurt) before bed provides sustained amino acid delivery during overnight fasting. Studies show this improves overnight muscle protein synthesis and recovery without causing fat gain.

Best Protein Sources

Lean meats: Chicken breast (31g per 100g cooked), turkey breast (30g), lean ground beef 93% (26g), pork tenderloin (26g). These provide high protein density with moderate fat content.

Fish and seafood: Salmon (25g per 100g), tuna (30g), shrimp (24g), cod (23g). Fish provides high-quality protein plus omega-3 fatty acids (particularly salmon, mackerel, and sardines).

Eggs: 6g per large egg, with one of the highest bioavailability scores of any protein source. The yolk contains most of the nutrients (vitamins A, D, B12, choline) — don't skip it unless you're specifically limiting dietary cholesterol.

Dairy: Greek yogurt (10g per 100g), cottage cheese (11g per 100g), whey protein powder (25g per scoop), milk (8g per cup). Dairy provides both whey (fast-digesting) and casein (slow-digesting) proteins.

Plant-based: Tofu (8g per 100g), tempeh (19g), lentils (9g per 100g cooked), chickpeas (7g), black beans (8g), edamame (11g), seitan (25g). Most plant sources have incomplete amino acid profiles — combining different sources throughout the day (rice + beans, hummus + bread) ensures complete coverage. Soy, quinoa, and buckwheat are naturally complete.

Protein supplements: Whey protein isolate is the most researched and bioavailable supplement. Casein provides slow-release protein (ideal before bed). Plant-based blends (pea + rice protein) offer comparable amino acid profiles to whey. Supplements are convenient but not superior to whole food sources — use them to fill gaps, not as a primary protein source.

Common Protein Mistakes

Eating too little protein is by far the most common mistake. The average American consumes approximately 0.5g per pound — adequate for sedentary health but insufficient for muscle building, optimal fat loss, or active lifestyles. Most people who start tracking protein are surprised by how much they need to add.

Backloading protein into a single meal. Eating 15g at breakfast and 15g at lunch, then 80g at dinner, is less effective than distributing evenly. Front-load protein — aim for at least 30g at breakfast. This often requires deliberate choices like eggs, Greek yogurt, or a protein shake rather than the typical carb-heavy breakfast.

Relying solely on protein supplements. Whole food sources provide micronutrients, fiber, and satiety that powders don't. Supplements should fill gaps — one shake per day supplementing 3–4 protein-rich meals is a reasonable approach. Three shakes replacing actual meals is not ideal.

Believing protein damages kidneys. This myth persists despite decades of research showing no kidney damage from high protein intake in healthy individuals. People with pre-existing chronic kidney disease should follow their doctor's protein recommendations, but for everyone else, intakes up to 1.5g/lb have shown no adverse kidney effects.