Health

Protein By Weight Calculator

Walk into any gym and ask five people how much protein they should eat, you'll get five different numbers — most of them either wildly optimistic or RDA-minimum boring. The actual research-backed targets are well established: roughly 0.7 g/lb for active maintenance, 1.0 g/lb when cutting fat (to preserve lean mass in a deficit) or bulking (to support muscle protein synthesis). This calculator gives you a daily protein target in grams based on body weight and goal, plus a clean per-meal breakdown for 4 or 5 meals per day — the spacing that maximizes muscle protein synthesis through the day.

Protein (g/day)

—

g/kg: —
Per meal (4x): —
Per meal (5x): —

The targets and why

Sedentary adults: 0.36 g/lb (the basic RDA, roughly 0.8 g/kg). 170-lb person = ~60 g/day. Survival-level, prevents protein deficiency but doesn't support performance.
Active maintenance: 0.7 g/lb. 170-lb person = ~120 g/day. Adequate for moderate strength training and general fitness.
Cutting (fat loss): 1.0 g/lb. 170-lb person = 170 g/day. Higher protein protects lean mass when you're in a calorie deficit, plus it's the most satiating macro — hunger management bonus.
Bulking (muscle gain): 1.0 g/lb. Same 170 g/day for the 170-lb person. Going higher (1.2-1.5 g/lb) doesn't add muscle faster; the rate-limit is training stimulus, not protein intake.

For obese or significantly overweight individuals, use lean body mass (or goal body weight) instead of total weight — you don't need 250 g of protein because you're carrying extra fat. A 250-lb person with 30% body fat has 175 lb of lean mass; 1.0 g per lb of lean mass = 175 g protein.

Why spread protein across meals?

Muscle protein synthesis (MPS) is triggered by a protein meal, peaks at ~2 hours, returns to baseline at ~4-5 hours. A single 150g protein dump at dinner produces one big MPS spike. The same 150g spread across 4-5 meals produces 4-5 spikes, leading to roughly 20-25% more total daily MPS over time.

The per-meal threshold for maximum MPS in healthy adults is ~30-40 g of complete protein (or ~0.4 g/lb body weight per meal). Less than that and you don't fully trigger MPS; more than that and the excess goes to maintenance, energy, or excretion. The sweet spot: 4 meals of 35-40 g, or 5 meals of 30 g.

How to use this calculator

Body weight in pounds (use lean body mass if significantly overweight).
Goal: sedentary (basic minimum), maintain (active), cut, or bulk.
Output: daily protein target in grams, grams per kilogram body weight, and per-meal breakdown for 4 and 5 meals.
Track your intake for a week using a food log app (MyFitnessPal, Cronometer) — most people significantly underestimate their actual protein intake.

Common scenarios

170-lb male, lifting 4x/week, cutting for summer. 170 g protein/day. 4 meals × 42g: 7 oz chicken breast (47g), 8 oz Greek yogurt with whey scoop (40g), 6 oz beef + 2 eggs (45g), tuna salad with cottage cheese (40g). Trackable, satiating, hits target.

140-lb female, casual gym 2x/week, maintaining. 0.7 × 140 = 98 g/day. 4 meals × 25g: easy day. Eggs at breakfast (15g) + Greek yogurt snack (15g) + chicken salad lunch (30g) + 5 oz salmon dinner (35g) = 95g. Done.

250-lb male, bulk phase. 1.0 × 250 = 250 g/day. 5 meals × 50g requires real planning. Whey protein shake (25g per scoop) twice/day as supplements; rest from whole foods. Common at this volume: ground beef + rice meals, chicken thigh + potato meals, lots of dairy.

FAQ

Can I eat too much protein? +

For healthy kidneys, protein up to 1.5 g/lb (3.3 g/kg) shows no harm in well-controlled studies. People with pre-existing kidney disease should consult a doctor before high-protein diets. The bigger practical risk of overshooting protein is crowding out carbs and fats, not the protein itself.

Does timing matter — protein right after the workout? +

The "anabolic window" panic is mostly myth. The actual window is more like 4-6 hours of elevated MPS post-training. As long as you hit your daily total spread across meals, exact post-workout timing isn't critical. Convenient (shake after gym) is fine; mandatory it isn't.

Whey, casein, plant — does the source matter? +

For total grams: not much. Whey is fast-digesting and high in leucine (the primary MPS trigger); casein is slow-release (good before bed). Plant proteins (pea, soy, rice) are slightly less efficient per gram — the practical fix is to eat 10-15% more protein on a plant diet. Plant blends (pea + rice) approach whey's amino profile.

How do I count protein in real foods? +

Quick references: 1 oz cooked chicken/beef/fish = 7-8 g protein. 1 large egg = 6 g. 1 cup cottage cheese = 25 g. 1 cup Greek yogurt = 17-20 g. 1 scoop whey = 20-25 g. 1 cup cooked rice = 5 g (yes, even "non-protein" foods add up). Reading labels: total grams per serving, not %DV (the DV is set at 50g/day which is absurdly low for most adults).

Do I need supplements? +

Only if hitting target with whole food is impractical for your schedule or appetite. Whey protein is the cheapest, easiest, most-studied option — $1-2 per 25g serving. Casein for slow-release evening dosing. Plant protein for vegan diets. Whole-food-only is fine if you can hit target.

What about elderly people? +

Protein needs go UP with age — anabolic resistance means older adults need more protein per meal to trigger MPS (closer to 35-40g/meal vs 25-30g in younger adults). Total daily protein for active 65+ adults: 1.0 g/lb or even slightly higher. Sarcopenia (age-related muscle loss) is heavily mediated by inadequate protein intake.

Why is the RDA so much lower than these numbers? +

The 0.8 g/kg RDA is set to prevent deficiency in 97.5% of sedentary adults — it's a minimum-to-avoid-disease number, not an optimum-for-performance number. Sports nutrition organizations (ISSN, ACSM) all recommend higher targets (1.4-2.2 g/kg) for active individuals.

What if I'm vegetarian or vegan? +

Same total targets, slightly different planning. Plant proteins are typically lower per serving and less complete amino acid profile per source. Combine pulses + grains (rice + beans, hummus + pita), use soy products (tofu, tempeh, edamame), and consider a plant protein powder. Vegans typically need to plan protein more deliberately than omnivores; it's totally achievable.