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BeHabitual

Macro calculator

Turns a calorie target into grams of protein, carbs, and fat.

Runs in your browser. Nothing is sent, saved, or shared.

kcal

Your maintenance, deficit, or surplus target.

kg

Used to sanity check the protein figure.

Protein first. The carb and fat balance is mostly preference.

Protein

165g

660 kcal

Carbs

220g

880 kcal

Fat

73g

657 kcal

Round these hard. Within about ten grams is close enough, and chasing exact numbers is what makes food miserable.

A plate divided between protein, grains, and vegetables

Protein first, then the rest

Of the three macros, protein is the one worth setting deliberately. It preserves muscle in a deficit, it is the most filling per calorie, and it costs the most energy just to digest. Get it right and the split between carbs and fat matters far less than the internet suggests.

The usual target sits between 1.6 and 2.2 grams per kilogram of body weight for anyone training. Below about 1.2 you start losing muscle alongside fat when cutting, which is the outcome nobody wants.

Carbs against fat is mostly preference

Once protein is set and calories are fixed, the remaining split is a question of what you find easy to eat and what makes you feel good training. Low carb suits some people and makes others miserable in the gym.

There is no metabolic advantage worth chasing here at equal calories and protein. Pick the split you will still be following in six weeks, which is the only property of a diet that reliably predicts anything.

Why the grams look oddly precise

They are calculated exactly, and you should round them hard. Hitting 147 grams of protein rather than 150 changes nothing you could measure.

Treat the numbers as a target zone of about ten grams either side. Chasing exact figures is the fastest way to make food miserable, and misery is what ends the plan.

How to calculate your macros

  1. 1

    Start from a calorie target

    Use your maintenance figure, or a deficit or surplus if you are changing weight. The calorie calculator works this out.

  2. 2

    Enter your body weight

    Protein scales with body mass, so this sets the floor before anything else is divided up.

  3. 3

    Pick a split

    Balanced suits most people. High protein helps in a deficit. Low carb is a preference rather than an advantage.

  4. 4

    Round the results

    Aim within about ten grams. Precision beyond that is invented accuracy.

Questions people ask

How many grams of protein should I eat?
Between 1.6 and 2.2 grams per kilogram of body weight covers most people who train. Higher within that range helps when you are in a calorie deficit, because it protects muscle while you lose fat.
What is a good macro split?
A common balanced split is 30 percent protein, 40 percent carbs, 30 percent fat. Once protein and calories are set, the carb and fat balance is largely preference and makes little measurable difference.
Do I need to hit my macros exactly?
No. Within about ten grams is close enough. Chasing exact numbers makes eating tedious, and a plan you abandon is worse than one you follow approximately.
How many calories are in each macro?
Protein and carbohydrate provide about 4 calories per gram, and fat about 9. That ratio is what the split calculation is built on.

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