Macro Calculator
Calculate your daily macronutrient targets, protein, carbs, and fat, based on your goals.
At 2,000 calories with a 30/40/30 split: 150g protein, 200g carbs, 67g fat per day.
Why This Calculation Matters
The Macro 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.
Macronutrient Basics
- Protein: 4 calories per gram, builds and repairs muscle
- Carbohydrates: 4 calories per gram, primary energy source
- Fat: 9 calories per gram, hormones, brain function, satiety
Common Macro Splits
- Balanced: 30% protein, 40% carbs, 30% fat
- High Protein: 40% protein, 30% carbs, 30% fat
- Keto: 20% protein, 5% carbs, 75% fat
- Endurance: 20% protein, 55% carbs, 25% fat
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?
For general health: 0.8g per kg of body weight. For muscle building: 1.6-2.2g per kg. For weight loss while preserving muscle: 1.2-1.6g per kg. Athletes and frequent exercisers should aim for the higher end.
Should I use the Macro 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 Macro 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.
Related Calculators
More Health →Calorie Intake Calculator
Calculate how many calories you should eat daily based on your goals, lose, maintain, or gain weight.
TDEE Calculator
Calculate your Total Daily Energy Expenditure, the total calories you burn each day including activity.
Macro Ratio Calculator
Find the ideal protein, carb, and fat ratio for your specific fitness goal.
Key terms
- Total Daily Energy Expenditure (TDEE)The total calories you burn in a typical day, including BMR plus energy spent on movement, digestion, and exercise. TDEE = BMR × activity multiplier, where mult…
- MacronutrientsThe three energy-providing nutrient categories: protein (4 calories per gram), carbohydrates (4 calories per gram), and fat (9 calories per gram). The Institute…
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.