Protein Calculator
Calculate your daily protein needs based on body weight, activity level, and goals. Free protein calculator with gram targets and food sources.
Protein at a glance
This page works the target the other way around: instead of quoting a population average, the Protein asks for your age and body weight, then scales the reference guidance to your own circumstances. Every number this page produces traces back to the reference values in the lead paragraph - the calculator adjusts WHO-table guidance by life stage, it never substitutes different source data.
Calculate your daily protein needs based on body weight, activity level, and goals. Free protein calculator with gram targets and food sources.
If you log meals, this is the companion number: it uses the same units and daily framing as the diary, which makes comparing your intake against the target a one-glance check rather than a conversion exercise.
About the Protein Calculator
This calculator provides evidence-based targets and interpretation based on current nutritional science and dietary guidelines. The formulas and reference ranges used are drawn from authoritative sources including the National Academies of Sciences, Engineering, and Medicine (Dietary Reference Intakes), the USDA Dietary Guidelines for Americans 2025-2030, and peer-reviewed research published in journals such as the American Journal of Clinical Nutrition, the New England Journal of Medicine, and JAMA.
How this calculator works
The calculator multiplies your body weight by an activity-specific multiplier (1.0 g/kg for sedentary adults, 1.4 g/kg for recreational exercisers, 1.6 g/kg for endurance athletes, 2.0 g/kg for strength athletes, and 2.2 g/kg when training in a calorie deficit) to compute a daily protein target in grams, then distributes that total evenly across the number of meals you select. The per-kilogram factors reflect current International Society of Sports Nutrition and American College of Sports Medicine position stands. The calculator does not estimate body fat or lean body mass, it uses total body weight only, so very lean and very high-body-fat individuals may want to adjust the target manually. Always interpret results in the context of your overall health, diet, and lifestyle, a single number rarely tells the full story.
Practical guidance
Use this calculator as a starting point for understanding your nutritional needs or health metrics. The results are educational, not diagnostic, always discuss significant findings with your healthcare provider before making changes to your diet, supplement regimen, or medication. For best results, recalculate periodically as your body composition, activity level, or health status changes. Track trends over time rather than focusing on single measurements, as day-to-day variation is normal and expected.
Evidence base and limitations
All nutritional targets are based on population-level recommendations that apply to most healthy individuals. Individual needs may vary based on genetics, medical conditions, medications, pregnancy, lactation, and other factors. The calculators do not replace professional medical or nutritional advice. If you have a chronic health condition, are pregnant or breastfeeding, or take medications that affect nutrient metabolism, consult a registered dietitian or physician for personalized guidance.
Formula sources, population limits, and references for this macronutrient calculator are documented in our public methodology. Read the methodology · Medical disclaimer