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Protein Intake Calculator

Calculate your recommended daily protein intake based on body weight and activity.

Units

Result

Recommended Protein
102 g/day
200150100500Grams/day: 58Grams/day: 102Grams/day: 145SedentaryModerately ActiveAthlete

About the Protein Intake Calculator

Protein needs vary significantly based on activity level - someone strength training regularly needs substantially more than a sedentary person. Our Protein Intake Calculator estimates a target based on your body weight and activity level.

How It Works

The calculator applies a protein factor per kilogram of body weight based on activity level - roughly 0.8 g/kg for sedentary individuals, 1.4 g/kg for moderately active people, and up to 2.0 g/kg for athletes and those strength training regularly.

Protein (g/day) = weight(kg) × activity factor

Formula & Methodology

Sports nutrition research consistently shows that regular resistance training and endurance exercise increase the body's protein needs above sedentary baselines, both to repair exercise-induced muscle damage and to support adaptations like increased muscle mass - this is why the per-kilogram factor scales up meaningfully with activity level, roughly doubling from sedentary (0.8 g/kg, the minimum to prevent deficiency) to serious athletic training (up to 2.0 g/kg).

Step-by-Step: Calculating It By Hand

  1. 1Convert body weight to kilograms if needed.
  2. 2Select the activity factor matching your typical training intensity and frequency.
  3. 3Multiply body weight in kilograms by that factor to find daily protein target in grams.

Examples

Moderately active

A 160 lb (72.6 kg) moderately active person has a recommended protein target around 102g/day.

Athlete or strength training

The same body weight at the athlete factor (2.0 g/kg) nearly doubles the target to about 145g/day, reflecting the higher protein needs of regular strength training.

Advantages

  • Scales protein recommendation to activity level, not a flat one-size-fits-all number
  • Based on commonly cited sports nutrition research ranges
  • Simple calculation from just body weight and activity category
  • Useful starting point for meal planning and tracking

Common Mistakes

  • Using a sedentary protein factor while training intensely, which can leave protein intake too low for recovery and muscle maintenance
  • Assuming more protein is always better beyond what activity level and goals actually require
  • Not adjusting the target after a significant change in training intensity or body weight
  • Confusing total protein needs with protein per meal, which is a separate consideration

Edge Cases to Watch For

  • The 0.8 g/kg sedentary baseline reflects the minimum to prevent deficiency, not necessarily an optimal amount for body composition or long-term health, which many nutrition researchers now argue is somewhat higher even for inactive adults.
  • This scales with body weight, not lean body mass - for individuals with higher body fat percentages, using lean mass instead of total weight can produce a more targeted protein figure.
  • Protein needs during active weight loss are often higher than maintenance needs at the same activity level, since adequate protein helps preserve lean mass during a calorie deficit.
  • Distribution across meals (rather than one large serving) is generally considered important for muscle protein synthesis, a factor this daily-total calculation doesn't address.

Common Use Cases

  • Setting a daily protein target based on activity level
  • Planning meals and food tracking to hit a protein goal
  • Adjusting nutrition around a new training program
  • General fitness and nutrition planning
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Why does protein need scale with body weight rather than calories?

Muscle maintenance and repair scale with lean body mass, not total energy intake, so protein recommendations are typically given per kilogram of body weight rather than as a percentage of calories.

Conclusion

Protein needs genuinely scale with activity level - a target that works for a sedentary lifestyle likely falls short during regular strength training. Our Macro Calculator can help fit this protein target into a complete daily macro plan alongside carbs and fat.