🍱 Macro Calculator — Protein, Carbs & Fat from Your Calorie Target
Enter your daily calorie target, pick a goal (Cut, Maintain, or Bulk), choose a macro ratio preset — Balanced 40/30/30, High-Protein 40/40/20, Low-Carb/Keto 20/25/55, High-Carb 55/20/25, or a fully custom split — set how many meals you eat, and hit Calculate. You instantly get grams of protein, carbs, and fat per day and per meal. Everything runs in your browser with no data sent to any server, completely free and no login required.
Protein and carbs = 4 kcal/g; fat = 9 kcal/g.
About
This IIFYM-style macro calculator applies the standard calorie-to-gram conversion: protein and carbohydrates each provide 4 kcal per gram, while fat provides 9 kcal per gram. It divides your adjusted calorie total (after applying a -500 kcal cut deficit or +300 kcal bulk surplus) by those energy densities to produce daily gram targets. Four ratio presets cover the most common nutrition approaches: Balanced (40/30/30 carb/protein/fat), High-Protein (40/40/20), Low-Carb/Keto (20/25/55), and High-Carb (55/20/25 for endurance athletes). A custom mode lets you enter any split that sums to 100%. Per-meal targets divide the daily totals evenly across 2 to 6 meals. All computation is client-side — no data is stored or transmitted.
How to use
- Enter your daily calorie target (kcal) in the first field. Use a number you know or get your TDEE first from the Calorie / TDEE Calculator.
- Choose your goal: Cut applies a -500 kcal/day deficit, Maintain uses your target as-is, and Bulk adds +300 kcal/day surplus.
- Select a macro ratio preset — Balanced (40/30/30), High-Protein (40/40/20), Low-Carb/Keto (20/25/55), High-Carb (55/20/25) — or click Custom and enter your own carb/protein/fat percentages that must total 100.
- Set the number of meals per day (2 to 6) to get an even per-meal breakdown alongside your daily totals.
- Click Calculate Macros. Your daily and per-meal grams of protein, carbs, and fat appear instantly — along with the calorie count and percentage for each macro.
FAQ
- What are macronutrients (macros)?
- Macronutrients are the three main nutrients your body uses for energy: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g). Tracking their gram intake — not just total calories — is the basis of flexible dieting (IIFYM) and most structured nutrition plans.
- How is this different from the Calorie / TDEE Calculator?
- The Calorie / TDEE Calculator tells you how many total calories to eat each day (your energy expenditure). This Macro Calculator takes that calorie number as its starting point and splits it into specific gram targets for protein, carbs, and fat. Use the TDEE tool first to find your calorie target, then use this tool to plan your macros.
- Which macro ratio preset should I choose?
- Balanced (40/30/30) is a good all-purpose starting point. High-Protein (40/40/20) suits those prioritizing muscle gain or retention. Low-Carb/Keto (20/25/55) is designed for fat-burning or low-insulin approaches. High-Carb (55/20/25) fits endurance athletes with high carbohydrate demands. Custom lets you enter any split that totals 100% to match a specific dietary protocol.
- Is this macro calculator free and does it store my data?
- Yes, completely free — no account, subscription, or hidden fees. Your calorie target and selections are saved locally in your browser's localStorage so they persist between visits. No data is ever sent to any server; everything stays on your device.
- What if my custom percentages don't add up to 100?
- The tool validates your custom split in real time and shows an error message indicating the current sum. Calculation is blocked until the three percentages add up to exactly 100. This ensures the gram targets always account for 100% of your calories with no rounding gap.