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Macro Calculator

Protein, carbs, fat — in grams, for your goal.

Calories set the rate of change; protein determines what you're changing. Nail those two and the carb/fat split is mostly preference. This calculator sets protein by body weight (the most evidence-backed approach), allocates a healthy fat floor, and assigns the rest to carbs — adjusting each preset for cut, maintenance, or bulk goals.

Daily macros
135P / 285C / 80Fgrams
Protein
135 g(540 kcal)
Carbs
285 g(1140 kcal)
Fat
80 g(720 kcal)
Per meal (×4)
34P / 71C / 20F

Protein set at 1.8 g/kg for maintain. Fat at 30% of calories. Carbs fill the rest.

Why protein is calculated per kilogram, not as a percentage

Most macro calculators set protein as a percentage of total calories. The problem: protein needs are tied to muscle mass (which tracks body weight), not to how many calories you eat. Eat more to bulk and a percentage-based calculator inflates your protein target needlessly. Eat less to cut and it shrinks it right when you need it most.

The evidence-based approach: anchor protein to body weight. For cuts, 2.0–2.2 g/kg is effective. For maintenance and lean bulks, 1.6–2.0 g/kg is sufficient. Research consistently shows that going above 2.4 g/kg produces diminishing returns for most natural trainees.

Carbs vs fat — which macro should you prioritize?

For body composition, the carb/fat split doesn't matter much — at matched calories and protein, results are similar. What matters is what supports your training and lifestyle.

  • Higher carbs (40–50% of calories): better performance in strength and endurance training. Glycogen is the primary fuel for high-intensity exercise.
  • Higher fat / lower carb (20–30% carbs): some people feel better cognitively on lower carbs; useful for very sedentary days or if carb-heavy foods trigger overeating.
  • The floor: don't drop fat below 20% of total calories for extended periods — you risk testosterone suppression and deficiencies in fat-soluble vitamins (A, D, E, K).
  • For most active people: protein first, fat at 25–30%, carbs for the rest. Adjust based on how your training feels.

Macro targets by goal

The calculator's presets follow mainstream sports nutrition guidelines.

  • Cut: protein 2.2 g/kg (high to preserve muscle in deficit), fat 25% of calories, carbs fill the gap.
  • Maintain: protein 1.8 g/kg, fat 30% (slightly higher for satiety and hormones at maintenance), carbs fill the gap.
  • Lean bulk: protein 2.0 g/kg, fat 25%, carbs fill the gap. Higher carbs supports training volume and recovery.
  • Per-meal guidance: dividing daily targets by 4 (four meals) is shown in the results as a practical starting point. Meal timing and frequency matter less than total daily intake.

How to set your daily macros

  1. 1
    Calculate your TDEE first
    Your macro targets are only meaningful relative to a calorie target. Use the TDEE calculator to find your maintenance calories, then apply a cut or bulk adjustment before entering here.
  2. 2
    Enter your calorie target and body weight
    Use your adjusted target (not TDEE if cutting or bulking). Body weight should be current morning weight in kg.
  3. 3
    Select your goal
    Cut, maintain, or lean bulk. This adjusts the protein per-kg multiplier and fat percentage.
  4. 4
    Use the per-meal breakdown
    The result shows per-meal targets assuming 4 meals. This is a starting template — adjust around your schedule and food preferences.
  5. 5
    Track for consistency, not perfection
    Hitting within ±10% on protein and ±5–10% on total calories is good enough. Macro tracking works best as a calibration tool for 4–8 weeks, then intuitive eating once you've internalized your portions.

FAQ

How much protein do I actually need?
For body recomposition: 1.6–2.2 g/kg body weight. Use the higher end (2.0–2.2 g/kg) during a calorie deficit to preserve muscle. Going above 2.4 g/kg provides minimal additional benefit for most people.
Should fat or carbs be the flexible variable?
Keep protein fixed by body weight first, set fat to 20–30% of total calories (needed for hormones and fat-soluble vitamins), then let carbs fill the remaining calories. This structure protects muscle and health while leaving flexibility in the carb/fat split.
Do macro splits really matter?
Total calories and protein intake matter most. Beyond that, the carb/fat split is flexible — low-carb and higher-carb approaches produce similar fat loss at equal calories and protein. However, higher carbs support performance in heavy lifting and endurance sessions, while lower carbs may suit sedentary days.
What does IIFYM mean?
If It Fits Your Macros — a flexible dieting approach where you can eat any food as long as it fits your daily protein, carb, and fat targets. Research supports this as equally effective as rigid 'clean eating' for body composition, with better long-term adherence for most people.
How many grams of fat per day?
This calculator sets fat at 25–30% of total calories depending on goal. For a 2,400 kcal diet, that's about 67–80 g of fat per day. Going below 20% of calories from fat for extended periods can suppress testosterone and fat-soluble vitamin absorption.

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