Protein Calculator

Find out exactly how much protein you need each day based on your weight, activity level, and goal — whether you're building muscle, losing fat, or maintaining fitness.

Enter your weight to calculate protein needs.

How it works

How protein needs are calculated.

  1. 01

    Base on body weight, not calories

    Protein targets are expressed per kilogram of body weight (g/kg) rather than as a percentage of calories. This is more precise — calorie intake fluctuates, but your lean mass (the tissue that actually needs protein) stays relatively constant. The RDA minimum is 0.8 g/kg for sedentary adults, established to prevent deficiency. Active people, however, need considerably more: research shows 1.6–2.2 g/kg maximizes muscle protein synthesis.

  2. 02

    Adjust for activity level

    Activity level matters because exercise breaks down muscle tissue, which protein rebuilds. Sedentary (0.8–1.0 g/kg): minimal breakdown. Lightly active (1.0–1.2 g/kg): moderate repair needed. Moderately active (1.2–1.6 g/kg): regular breakdown and rebuild cycle. Very active / athletes (1.6–2.2 g/kg): high turnover requires ample protein for recovery and adaptation. Beyond 2.4 g/kg, extra protein is converted to glucose or excreted — no benefit to muscle.

  3. 03

    Further adjust for your goal

    Weight loss increases protein needs: to preserve muscle in a caloric deficit, aim for the high end (1.8–2.4 g/kg). Higher protein also increases satiety and thermogenesis, helping fat loss. For muscle building: 1.6–2.2 g/kg covers the range where muscle protein synthesis is maximized (per Morton et al., 2018 meta-analysis). For maintenance: 1.2–1.6 g/kg is sufficient. Distribute intake across meals — 20–40g per meal maximizes anabolic signaling.

FAQ

Frequently asked questions.

How do I calculate how much protein I need?

Multiply your body weight in kg by the g/kg factor for your goal. For pounds, multiply by the g/lb factor. Example: 75 kg person building muscle at 2.0 g/kg = 150 g protein/day. For imperial: 165 lb × 0.91 g/lb = 150 g/day. RDA minimum for sedentary adults is 0.8 g/kg. Active people need 1.2–1.6 g/kg; muscle builders and people in a fat-loss deficit need 1.6–2.2 g/kg. Spread intake across 3–5 meals with 20–40g per meal for best absorption.

Is 100g of protein a day too much?

For most people, 100g/day is not too much — it's actually a reasonable target. For a 70 kg (154 lb) active person, 100g equals 1.43 g/kg, which falls in the healthy moderate range. For a smaller, sedentary person (50 kg), 100g is 2.0 g/kg — on the higher end but still safe for healthy adults. Protein only becomes excessive above ~3 g/kg for extended periods, and mainly poses risk to those with pre-existing kidney disease. If 100g fits your calorie budget, it's a solid intake for most goals.

How much protein should I eat a day to lose weight?

For fat loss, target 1.6–2.4 g/kg of body weight — higher than maintenance. High protein in a caloric deficit preserves lean muscle, boosts satiety (keeping you fuller longer), and increases thermogenesis (protein burns more calories during digestion than carbs or fat). Example: a 75 kg woman in a deficit should aim for 120–180g protein/day. Keep total calories below TDEE while hitting this protein target, then fill remaining calories with carbs and fat based on preference.

How much protein should a 200-pound woman have?

A 200-pound (91 kg) woman's protein target depends on activity and goal. Sedentary: 73g/day (0.8 g/kg). Moderately active / maintenance: 109–145g (1.2–1.6 g/kg). Fat loss: 164–218g (1.8–2.4 g/kg). Muscle gain: 145–200g (1.6–2.2 g/kg). Most active women at 200 lb do well hitting 140–160g/day as a practical all-purpose target — it covers maintenance and supports both fat loss and body recomposition.

How much protein do I need to build muscle?

Research consistently shows 1.6–2.2 g/kg of body weight (0.73–1.0 g/lb) maximizes muscle protein synthesis. Going above 2.2 g/kg provides no additional muscle-building benefit — extra protein is used for energy or excreted. Distribute intake across meals: aim for 20–40g per meal across 4–5 meals to maximize the anabolic response per session. Total daily intake matters more than precise timing.

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Last updated: July 28, 2026