Free Macros Calculator
Updated September 2026
Calculate daily macronutrient targets (protein, carbs, fat) in grams from your daily calorie target and goal: fat loss, maintenance, or muscle gain — free online.
Verified Capabilities
Converts a calorie target into protein, carb, and fat grams and percentages with a visual bar.
Lose Weight, Maintain Weight, and Gain Muscle each apply a different, nutrition-informed macro split.
Download your macro breakdown as a CSV or plain-text file.
Does not calculate TDEE from age/gender/height/weight/activity — you must already know your daily calorie target. There's also no custom macro-split option beyond the 3 fixed presets.
Understanding your health numbers is the foundation of informed wellness decisions. The Macro Calculator uses clinically established formulas to provide science-backed estimates.
Calculate daily macronutrient targets (protein, carbs, fat) in grams from your daily calorie target and goal: fat loss, maintenance, or muscle gain — free online. Results are immediate — no waiting, no loading screens, no account required.
Who uses the Macro Calculator?
- Gym-goers who already know their calorie target and want a quick protein/carb/fat breakdown.
- Competitive athletes dialing in nutrition for a cutting or bulking phase.
- Health-conscious people learning to balance macronutrients for sustained energy.
Common uses and search terms
The Macro Calculator is frequently used for: macros, protein carb fat, macronutrients. Whether you need a quick result or are working through a longer project, the tool handles all common variations without any configuration.
Why use Allio Tools's Macro Calculator?
All calculations run locally. No personal health data is ever transmitted or stored anywhere. The tool is completely free with no usage limits, no premium tiers, and no account required. Available in 11 languages and optimised for all screen sizes, the Macro Calculator works on desktop, tablet, and mobile with no app download needed.
See also:BMI Calculator · TDEE Calculator · Calorie Calculator
How the Macro Calculator works
Enter your daily calorie target (find this first using the TDEE Calculator or Calorie Calculator if you don't already know it).
Select your goal: Lose Weight, Maintain Weight, or Gain Muscle — each uses a different fixed protein/carb/fat split.
Results update automatically, showing grams and percentages for protein, carbohydrates, and fat, plus a visual bar breakdown.
Download your results as CSV or Text for reference.
Tips & tricks
- This tool doesn't calculate TDEE — you need your daily calorie number ready before using it. Get that from the TDEE Calculator or Calorie Calculator first.
- The three goal options use fixed percentage splits; there's no custom split input for a specific ratio like a strict keto diet.
- Results update live as you type your calorie number or change your goal — no need to click Calculate again.
Frequently Asked Questions
Does this tool calculate my TDEE from my age, gender, height, and weight?
No — you need to enter your daily calorie target directly. This tool only splits an already-known calorie number into protein/carb/fat grams; it doesn't compute TDEE itself. Use the TDEE Calculator or Calorie Calculator first to get that number.
How much protein do I need per day?
For muscle building: 0.7–1.0g per pound of bodyweight (1.6–2.2g per kg). For fat loss while preserving muscle: 0.8–1.2g per pound. For general health: 0.36g per pound (0.8g per kg) is the RDA minimum.
Can I choose my own custom macro split (like a specific keto ratio)?
No — there are only three fixed splits, one per goal: Lose Weight (40% protein / 35% carb / 25% fat), Maintain Weight (30% protein / 45% carb / 25% fat), and Gain Muscle (35% protein / 45% carb / 20% fat). There's no way to enter a custom percentage split.
Do carbohydrates make you gain fat?
Excess calories cause fat gain, not carbs specifically. Carbohydrates are the primary fuel for high-intensity exercise and brain function. Restricting carbs can help with fat loss for some people through appetite reduction and adherence, not metabolic magic.
How do I track my macros?
Use a food tracking app (MyFitnessPal, Cronometer, or Lose It!) to log meals. Weigh food with a kitchen scale for accuracy. Most people see results from tracking consistently for 4+ weeks rather than perfect accuracy from day one.
Is my data safe when using the Macro Calculator?
Completely safe. The Macro Calculator processes everything locally in your browser. No input data, results, or usage information is ever transmitted to or stored on any server.
How accurate are the Macro Calculator calculations?
The Macro Calculator uses clinically validated formulas such as the Mifflin–St Jeor or Harris–Benedict equations where applicable. Results are population-based estimates and can differ from measured values by 10–20% for individuals with atypical body composition. See our <a href="/methodology/">Methodology page</a> for full formula sources and references. Consult a qualified healthcare professional before making medical or dietary decisions.
Which formula does the Macro Calculator use?
The Macro Calculator uses an established, peer-reviewed formula endorsed by leading health organisations such as the WHO, CDC, or NIH where applicable. The specific formula is chosen for its validated accuracy across diverse adult populations under normal conditions.
Works with ChatGPT, Claude, Cursor, GitHub Copilot, VS Code, Poe and more — 106+ tools, zero data collection.