Protein Intake Calculator
Calculate your daily protein needs based on body weight, activity level, and fitness goals.
At 2,000 calories with a 30/40/30 split: 150g protein, 200g carbs, 67g fat per day.
Why This Calculation Matters
The Protein Intake Calculator turns a well-known health formula into an instant lookup. It's most useful when you're tracking a number over time or comparing yourself against published reference ranges from bodies like the CDC, NIH, or WHO. Use it as one data point among many, not a diagnosis.
How to Use This Calculator
- Enter your values in the input fields, each one has a label and help text explaining what to type.
- Results appear instantly as you type; there's no "calculate" button to press.
- Change any input to compare scenarios side by side.
All math happens in your browser. Nothing you type is sent to a server, saved, or shared.
Reading Your Result
A single number tells you less than a trend. Track this value over weeks or months rather than obsessing over day-to-day variation. Hydration, sleep, and timing can all shift short-term readings without reflecting any real change.
Protein Guidelines
- Sedentary adults: 0.8g per kg (RDA minimum)
- Active adults: 1.2-1.6g per kg
- Muscle building: 1.6-2.2g per kg
- Weight loss: 1.2-1.6g per kg (preserves muscle)
- Endurance athletes: 1.2-1.4g per kg
- Elderly: 1.0-1.2g per kg (prevents sarcopenia)
When to Use This Calculator
- Track personal health metrics over time alongside guidance from your clinician.
- Understand how lifestyle changes may influence a given health number.
- Compare values against recognized reference ranges from CDC, NIH, or WHO.
Limitations & Common Mistakes
- Not a substitute for medical advice. Always consult a qualified clinician for anything that affects your care.
- Population-level formulas don't account for individual medical history, medications, or body composition nuances.
- Reference ranges evolve, use current CDC/NIH/WHO values when accuracy matters.
Frequently Asked Questions
How much protein do I need per day?
The RDA minimum is 0.8g per kg of body weight, but this is for sedentary people. Active individuals should aim for 1.2-2.2g per kg depending on their goals. For a 160-lb (73 kg) person: minimum 58g, active 88-117g, muscle building 117-160g.
Should I use the Protein Intake Calculator for medical decisions?
No. This tool is educational. For anything affecting your health or treatment, consult a qualified clinician who can factor in your full medical history.
Which reference values does this use?
Where relevant, thresholds match CDC, NIH, or WHO guidance. Sources are linked in the "Sources & Further Reading" section below.
Is this calculator free to use?
Yes. The Protein Intake Calculator is free, requires no signup, and runs entirely in your browser, your inputs are never sent to a server.
How often is this calculator updated?
Formulas are reviewed against authoritative sources, and any rate or price data is refreshed on an automated schedule. Check the "as of" date on any live data panel for the most recent refresh.
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TDEE Calculator
Calculate your Total Daily Energy Expenditure, the total calories you burn each day including activity.
Related guides
- TDEE: The Only Calorie Number That Actually Drives Weight ChangeBMR tells you the baseline. Calorie intake tells you the input. TDEE is the number that decides whether you lose, maintain, or gain, and it is the one most people miscalculate.
- BMI vs. Body Fat Percentage: Which Number Actually Measures HealthBMI is free and fast. Body fat percentage is more accurate. Waist-to-hip ratio predicts cardiovascular risk better than either. Here is when to use which, and what the CDC and WHO actually recommend.