Guide · 5 min read

How to calculate macros

A simple, peaty guide to protein, fat, and carb targets, with the math for weight loss, muscle gain, recipes, and per-food servings.

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Step 1: get your calorie target (TDEE)

Macros sit inside a calorie target. Calculate your BMR (Mifflin-St Jeor if you don't know your body fat, Katch-McArdle if you do), multiply by 1.2 for the baseline, then add calories from steps, gym, sports, and a small climate factor. That total is your TDEE.

Adjust for your goal:

Lose fat: TDEE minus 10 to 25 percent
Maintain: TDEE
Lean bulk: TDEE plus 10 to 15 percent

BasedCal handles every step in one screen, including climate from your location.

Step 2: lock protein first

Set protein at about 1 g per pound of body weight (roughly 2.2 g per kg). That's enough to protect lean mass on a cut, support hypertrophy on a bulk, and keep your liver and connective tissue supplied.

Protein is 4 kcal per gram. For a 180 lb person, that's 180 g of protein, or 720 kcal accounted for before you think about fat or carbs.

Step 3: split the rest into fat and carbs

Subtract protein calories from your target. The remainder gets divided between fat (9 kcal/g) and carbs (4 kcal/g) based on the style you eat.

For a peaty / pro-metabolic split, keep fat low to moderate (saturated only: butter, ghee, dairy, coconut, beef tallow) and put most of the remainder into easy carbs: fruit, juice, milk, root vegetables, honey. High carb intake supports T3, body temperature, and recovery.

For a carnivore / Aajonus-style split, flip it: fat-dominant with raw dairy and animal fats, minimal carbs.

How to calculate macros in food and recipes

Per-food math is just linear scaling. Look up macros per 100 g, then multiply by (your grams / 100). For a recipe, sum the macros of every ingredient at raw weight, then divide by servings.

The BasedCal food logger does this for you, with a curated database of pro-metabolic and carnivore-friendly foods, plus live micronutrient tracking (calcium, magnesium, B12, choline, vitamin A, and more).

Frequently asked questions

How do you calculate macros from calories?+

Protein and carbs are 4 kcal per gram, fat is 9 kcal per gram. Pick your daily calorie target, lock protein first (about 1 g per lb of body weight), then split the leftover calories between fat and carbs. BasedCal does this automatically.

How do I calculate macros for weight loss?+

Start from your maintenance calories (TDEE), subtract 10 to 20 percent, keep protein high (1 g per lb body weight) to protect lean mass, then favor easy-to-digest carbs (fruit, dairy, root vegetables, honey) over PUFA-heavy fats. A mild deficit beats an aggressive one for energy and thyroid output.

How do I calculate macros for muscle gain?+

Add 10 to 15 percent on top of maintenance, keep protein at 1 g per lb, and put most of the surplus into carbs. Carbs spare protein, drive insulin and thyroid (T3), and give you the glycogen you actually train on.

How do I calculate macros in a recipe?+

Add up protein (g), fat (g), and carbs (g) for every ingredient at its raw weight, then divide by the number of servings. Multiply each macro by its kcal/g (4, 9, 4) to get calories per serving. The BasedCal food logger does this per meal automatically.

How do I calculate macros in food?+

Weigh the food in grams, look up per-100g values for protein, fat, and carbs, then scale linearly (your grams / 100). A 150 g serving of whole milk at 3.2 g protein per 100 g gives 4.8 g protein. The food logger handles the math and tracks micronutrients too.

What's the best macro split for a peaty / pro-metabolic diet?+

Protein around 1 g per lb body weight, fat low to moderate (saturated sources: butter, ghee, dairy, coconut), carbs high from fruit, juice, dairy, root vegetables, and honey. Avoid PUFA-heavy seed oils, nuts, and pork fat. The goal is high T3 and a warm, well-fed body.

Skip the math

BasedCal calculates BMR, TDEE, and macros from a single form, with a climate factor and Peaty / Aajonus presets built in.

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