Protein Calculator
Adjust the inputs below. Results update as you type.
How it works
General guideline: 0.8g/kg for sedentary adults (RDA); 1.2–2.0g/kg for active individuals. For muscle building: 1.6–2.2g/kg body weight. High protein during fat loss (2.0–2.4g/kg) preserves muscle mass. Protein has 4 kcal/gram. Sources: meat, eggs, dairy, legumes, tofu. Spreading intake across 3–5 meals may optimize muscle protein synthesis better than one large serving.
Input guidance
- Use measured values (recent weight, height, activity level) rather than guesses.
- Recalculate every few weeks as your routine and body metrics change.
- Pair screening metrics with context such as sleep, stress, and medical history.
The formula
Protein needs scale with body weight and activity: roughly 0.8 g/kg for sedentary adults, 1.2–2.0 g/kg for active people, and up to about 2.2 g/kg when building muscle in a deficit.
Worked example
An active 70 kg person at 1.6 g/kg needs about 112 g of protein per day, spread across meals.
More examples to test
- Maintenance case: keep activity constant and observe expected baseline ranges.
- Adjustment case: change only one major variable to understand sensitivity.
How to interpret results
Use results for awareness and planning, then validate with qualified medical or nutrition professionals for individualized decisions.
When this can be inaccurate
Population formulas cannot account for all biological factors such as medical conditions, medication effects, body composition differences, and genetics.
Change history
- July 2026: Quality-reviewed for publication with formula checks and explanatory copy updates.
Site-wide corrections also appear on the corrections log.
Track calories, macros, and fitness progress
General wellness resource.
Frequently asked questions
How much protein do I need?+
Sedentary adults need around 0.8 g/kg; active people and those building muscle benefit from 1.2–2.2 g/kg depending on goals and training.
Can I eat too much protein?+
Very high intakes are generally safe for healthy people but offer diminishing returns. Those with kidney disease should consult a doctor.
Does timing matter?+
Spreading protein across the day and including some after training supports muscle repair, though total daily intake matters most.
Can this calculator diagnose a condition?+
No. It is a screening and education tool only, not a clinical diagnosis.
When should I seek professional advice?+
Seek professional advice when results are extreme, persistent, or conflict with symptoms, goals, or prior medical guidance.
Guided next steps
Want the full workflow? Use this calculator inside a step-by-step guide.