Protein Calculator
Determine your optimal daily protein intake based on your body weight and activity level. See recommendations ranging from sedentary to competitive athlete levels, with targets in grams per day and per meal.
Protein is the macronutrient most tightly linked to body composition outcomes. Higher protein intake supports muscle building during strength training, preserves muscle during weight loss, increases satiety (helping with appetite control), and supports recovery from exercise and injury. The government's baseline recommendation — 0.36g of protein per pound of body weight (0.8g/kg) — is the bare minimum to prevent protein deficiency in sedentary adults. For active individuals, especially those trying to build muscle or lose fat, evidence-based recommendations are 2–4× higher.
Modern sports nutrition consensus, based on extensive research, suggests roughly: 0.6–0.8g per pound (1.4–1.7g/kg) for moderately active adults, 0.8–1.0g per pound (1.7–2.2g/kg) for those building muscle, and similar ranges for those losing weight while preserving muscle. Athletes in high-volume training, recovering from injury, or seniors fighting age-related muscle loss (sarcopenia) may benefit from the higher end of these ranges. For a 170-pound moderately-active adult building muscle, the target is roughly 136–170 grams per day — a meaningful amount that requires conscious meal planning.
This calculator estimates your daily protein target and per-meal target based on weight, activity level, goal, and number of meals. Use it as a planning anchor. Hitting the protein target consistently matters more than meal-to-meal precision — distributing protein roughly evenly across meals (20–40 grams each) is ideal but missing on any specific day or meal isn't consequential as long as the weekly average lands in range.
Inputs
Results
Daily Protein
85g
Per Meal
28g
Protein Calories
340 cal
Per Pound
0.5g/lb
1.1g/kg
Protein by Activity Level
Formula
How to use this calculator
- Enter your current body weight in pounds. Use actual weight (not "ideal" weight) for the calculation. For very high body fat, some sports nutritionists recommend using lean body mass instead, but for most people, total body weight is a reasonable basis.
- Select your activity level. Be honest — most people overestimate activity. "Moderate" means consistent gym attendance 3-4x/week with real intensity, not light or sporadic activity.
- Select your goal: weight loss (slight calorie deficit), maintenance (calorie balance), or muscle gain (slight calorie surplus). Higher protein supports each goal differently.
- Set number of meals per day. 3–4 is standard; some prefer 5–6 smaller meals (no metabolic advantage but may help with satiety or training volume).
- Review the daily protein target in grams and the per-meal target.
- Plan meals to hit the per-meal target consistently. Most people find it easier to plan one or two "protein-anchor" foods per meal (chicken breast, fish, eggs, Greek yogurt, lean beef, tofu) than to assemble protein from many smaller sources.
- Track for a week to see how close current intake is to target. Most adults eat far less protein than evidence-based recommendations — especially during weight loss when food volume drops.
- Re-run as body weight or activity changes. For substantial weight loss (15+ lbs), update the calculation to current weight.
Worked examples
Average sedentary adult
170-lb adult, sedentary, maintenance, 3 meals/day. Protein target: 170 × 0.5g/lb = 85g/day Per-meal target: ~28g per meal Hitting 28g of protein per meal is easy with a single solid protein source: a 4oz chicken breast (32g), a serving of Greek yogurt (20g) plus an egg (6g), or a small can of tuna (22g) with cottage cheese. This is well above the RDA baseline (0.36g/lb = 61g/day) but reflects modern evidence that higher intake supports satiety and body composition even without intense exercise.
Lifter in a fat loss phase
200-lb male, active (5x/week resistance + cardio), weight loss, 4 meals/day. Protein target: 200 × 1.1g/lb = 220g/day Per-meal target: ~55g per meal 55g per meal is substantial. Hitting it consistently requires deliberate planning: 6oz chicken breast (48g) plus a small Greek yogurt (15g), or 6oz lean beef (40g) plus a protein shake (24g). Higher protein during fat loss serves two purposes: (1) preserves muscle during the calorie deficit (the body otherwise sacrifices muscle along with fat), and (2) increases satiety, making the calorie deficit more tolerable.
Senior fighting age-related muscle loss
65-year-old, 160 lbs, light activity (walking, basic strength training 2x/week), maintenance, 3 meals/day. Protein target: 160 × 0.7g/lb = 112g/day (elevated to fight sarcopenia) Per-meal target: ~37g per meal Age-related muscle loss (sarcopenia) accelerates after 50 and is one of the major contributors to frailty and falls in seniors. Higher protein intake (combined with resistance training) is one of the most evidence-based interventions for preserving muscle mass with age. Many seniors eat well below this target — closer to 50-60g/day — and experience progressive muscle loss as a result. Conscious protein increase, often with whey protein supplementation, is widely recommended by gerontologists.
When to use this calculator
Use this calculator when starting a fitness or body composition program, after a weight loss plateau, when increasing training intensity, when recovering from injury or surgery, or simply when curious about whether current protein intake is adequate.
For weight loss specifically, higher protein has three benefits: it preserves muscle in the calorie deficit, increases satiety (making the deficit easier to sustain), and has a slightly higher thermic effect than carbohydrate or fat (uses more calories to digest). Dieters who hit 0.8-1.2g/lb consistently lose more body fat and less muscle than those eating closer to the RDA.
For muscle building, the protein target is one of the most important factors — though training stimulus (progressive overload) and adequate sleep matter as much. Higher protein supports muscle protein synthesis; without sufficient intake, even ideal training produces suboptimal results.
For seniors, fighting sarcopenia (age-related muscle loss) is one of the most important interventions for long-term health. Resistance training plus adequate protein (0.7g/lb or higher) preserves and can rebuild muscle mass into the 70s and 80s.
Pair this with the BMR, TDEE, calorie, and macro calculators for full nutritional planning. Protein is one of three macros (along with carbohydrates and fats) — total calories matter for weight management, but protein quality and amount drive body composition outcomes within any given calorie target.
Practical strategies for hitting protein targets:
1. **Anchor each meal with protein.** Decide the protein source first (chicken, fish, eggs, Greek yogurt, beef, tofu), then build the rest of the meal around it.
2. **Make breakfast count.** Many people eat low-protein breakfasts (cereal, toast, fruit). Adding eggs, Greek yogurt, cottage cheese, or a protein shake to breakfast often closes a large gap.
3. **Use whey protein strategically.** Whey protein powder is the most concentrated, cost-effective protein source. 1-2 scoops per day (24-48g protein) can bridge meals or fill the daily gap easily.
4. **Track for a week, then adjust.** Most people are surprised at how short of target they're running. Tracking apps (MyFitnessPal, Cronometer, MacroFactor) provide accurate per-food protein counts.
5. **Distribute reasonably.** Aim for 20-40g per meal across 3-5 meals. The "one massive protein meal per day" approach is suboptimal — body can't use more than ~40g per meal for muscle protein synthesis in a single sitting.
6. **Sustainability matters.** A diet you can't sustain is worse than one you can. If 1.0g/lb feels overwhelming, start at 0.7g/lb and build gradually.
Common mistakes to avoid
- Eating far less protein than evidence-based recommendations. Most U.S. adults eat 0.3-0.5g/lb — close to or below the RDA baseline, well below sports nutrition recommendations. The "average American diet" is protein-light by modern standards.
- Concentrating protein in one meal. Eating 80g of protein at dinner with minimal protein at other meals is suboptimal. Distribute 20-40g per meal across the day for best muscle protein synthesis.
- Underestimating muscle loss during weight loss. Aggressive calorie deficits combined with low protein intake lead to significant muscle loss along with fat loss. The scale shows weight loss, but body composition worsens. Higher protein protects muscle.
- Fearing kidney damage from high protein. For healthy adults, high protein intake (up to 1.5g/lb sustained) has not been shown to harm kidneys in research. The myth originated from misinterpreting research in pre-existing kidney disease populations.
- Avoiding protein supplements unnecessarily. Whey, casein, and plant proteins are processed foods but generally safe and convenient. Whole-food protein is preferable when practical, but supplements help close gaps that whole foods alone don't.
- Ignoring protein quality. Plant proteins (legumes, soy) are useful but generally have lower bioavailability and incomplete amino acid profiles compared to animal proteins. Vegetarians and vegans often benefit from slightly higher protein targets (10-20% more) to compensate.
Frequently Asked Questions
Sources & further reading
- Dietary Reference Intakes for Protein — U.S. National Academies / USDA National Agricultural Library
- Dietary Guidelines for Americans 2020–2025 — U.S. Department of Agriculture / U.S. Department of Health and Human Services
- Physical Activity Guidelines for Americans — U.S. Department of Health and Human Services