Calories

Macro Calculator: Macros for Weight Loss or Muscle Gain (2026 Guide)

Learn how macros work, how to set protein/fat/carbs for your goal, and how to avoid common macro mistakes. Includes a free macro calculator and links to maintenance calories and protein targets.

  • UpdatedJan 3, 2026
  • Reading time7 min read

Macro calculator: how to set protein, fat, and carbs

Macros are simply how your calories are split into:

  • Protein
  • Fat
  • Carbs

The “best” macro split is the one that supports your goal and adherence.

Quick macro calculator

The simplest macro approach (that works)

  1. Set a calorie target (maintenance or deficit/surplus).
  2. Set a protein floor.
  3. Set a minimum fat level.
  4. Put remaining calories into carbs.

Useful tools:

Common macro mistakes

  • No calorie target: macros without calories is guesswork.
  • Protein too low: makes dieting harder and recovery worse.
  • Fat too low: can harm satiety and adherence.
  • Daily perfection: weekly averages matter more.

Track results with measurements

If macros are dialed in but results look confusing, track more than weight: