Counting macros means tracking the three macronutrients in your food: protein, carbohydrates, and fat. Each one contains a set number of calories per gram, and by hitting specific gram targets for each, you control both your total calorie intake and the composition of your diet. The process comes down to four steps: figuring out how many calories you need, dividing those calories among protein, carbs, and fat, weighing or estimating your food, and logging it.
The Basic Math Behind Macros
Every food you eat is some combination of three macronutrients, and each carries a fixed calorie value. Protein has 4 calories per gram. Carbohydrates have 4 calories per gram. Fat has 9 calories per gram. That difference is why fat is often called “calorie-dense”: a tablespoon of olive oil packs more than twice the calories of a tablespoon of sugar, gram for gram.
These numbers are the conversion tool you’ll use constantly. If a food label says a serving has 20 grams of protein, 30 grams of carbs, and 10 grams of fat, you can calculate: (20 × 4) + (30 × 4) + (10 × 9) = 80 + 120 + 90 = 290 calories. That’s all macro counting really is: working backward and forward between grams and calories.
Step 1: Find Your Calorie Target
Your body burns calories through four channels: your basal metabolic rate (the energy needed just to keep you alive at rest), the thermic effect of food (energy spent digesting), non-exercise activity like walking around your house or fidgeting, and intentional exercise. Added together, these make up your total daily energy expenditure, or TDEE.
The simplest way to estimate your TDEE is with an online calculator that factors in your age, sex, height, weight, and activity level. These calculators aren’t perfectly accurate for any individual, but they give you a starting point. From there, you adjust based on your goal:
- Fat loss: Eat roughly 300 to 500 calories below your TDEE.
- Muscle gain: Eat roughly 200 to 400 calories above your TDEE.
- Maintenance: Eat at your TDEE.
A healthy rate of weight loss is about 0.5% to 1.0% of your total body weight per week. For a 180-pound person, that’s roughly 1 to 1.8 pounds weekly. Faster than that and you’re more likely to lose muscle along with fat.
Step 2: Set Your Macro Split
Once you have a calorie target, you divide it among protein, carbs, and fat. The right split depends on what you’re trying to do.
For weight loss, a common starting point is 25% to 30% of calories from protein, 40% to 45% from carbs, and 25% to 30% from fat. The protein is set higher than a typical diet because it helps preserve muscle in a calorie deficit and keeps you feeling fuller. For muscle gain, carbs climb to 50% to 60% to fuel training and recovery, with protein at 20% to 25% and fat at 20% to 25%. For maintenance, a balanced split of roughly 45% to 55% carbs, 20% to 25% protein, and 20% to 30% fat works well.
Here’s what that looks like in practice. Say your target is 2,000 calories for fat loss and you choose a 40/30/30 split (carbs/protein/fat):
- Carbs: 2,000 × 0.40 = 800 calories ÷ 4 = 200 grams
- Protein: 2,000 × 0.30 = 600 calories ÷ 4 = 150 grams
- Fat: 2,000 × 0.30 = 600 calories ÷ 9 = 67 grams
Those gram targets are what you track each day.
A Note on Protein
The government’s recommended dietary allowance for protein is 0.36 grams per pound of body weight, but that number represents the bare minimum to avoid deficiency, not an optimal intake. For anyone who exercises regularly or is trying to lose fat while preserving muscle, a more practical target is 0.7 to 1.0 gram per pound of body weight. For lean, trained individuals in a calorie deficit, research supports going even higher, up to about 1.0 to 1.4 grams per pound of lean body mass.
Step 3: Weigh, Measure, and Log Your Food
This is where the actual counting happens. You’ll need a food scale (a basic digital kitchen scale costs around $10 to $15) and a tracking app. Most apps have databases with hundreds of thousands of foods, so you search for what you’re eating, enter the amount, and the app logs the macros automatically.
Weigh foods raw whenever possible, since cooking changes the water content and weight. A raw chicken breast that weighs 6 ounces might weigh only 4.5 ounces after grilling, but the protein content is the same. If you log the cooked weight using the raw entry, your numbers will be off.
Nutrition labels are your best friend for packaged foods, and they’re generally reliable. NIST testing shows that macronutrient values on commercial labels are accurate to within about 2% to 5%. That’s close enough for practical tracking. Pay attention to serving sizes, though. A bag of chips might list a serving as 15 chips, but contain three servings. Weigh the portion rather than guessing how many chips you grabbed.
Net Carbs and Fiber
If you’re tracking carbs closely (especially on a lower-carb plan), you may want to calculate net carbs. The basic idea: fiber passes through your body without being fully absorbed, so many people subtract it. Net carbs = total carbs minus fiber. If a food also contains sugar alcohols, which are partially absorbed, subtract half the sugar alcohol grams from the total carbs rather than all of them. So a protein bar with 29 grams of total carbs and 18 grams of sugar alcohols would count as 20 net carbs (29 minus 9).
Step 4: Track Without a Scale
You won’t always have a food scale handy, and that’s fine. Your hands make surprisingly consistent measuring tools because they scale roughly with your body size. Use these as quick estimates when eating out or traveling:
- Your open palm (fingers excluded) is about 3 ounces of cooked meat, fish, or poultry, roughly 20 to 25 grams of protein.
- Your fist is about 1 cup, useful for measuring raw vegetables or a serving of rice or pasta.
- Your cupped palm is about half a cup, good for cooked fruit, beans, or starchy sides.
- Your thumb (tip to base) is about 2 tablespoons, the right amount for peanut butter or salad dressing.
- Your thumbnail is about 1 teaspoon, a standard serving of butter or oil.
Hand estimates won’t give you gram-level precision, but they keep you in the right ballpark on days when exact tracking isn’t practical. Most people find that a few weeks of weighing food at home trains their eye well enough to estimate portions with reasonable accuracy going forward.
How to Handle Alcohol
Alcohol doesn’t fit neatly into the three macros. It contains 7 calories per gram, but most tracking apps don’t have a separate “alcohol” category. The workaround is to log alcohol calories as either carbs or fat, or a mix of both. If a glass of wine has 120 calories, you can log it as 30 grams of carbs (120 ÷ 4), or as about 13 grams of fat (120 ÷ 9), or split it down the middle: 60 calories logged as 15 grams of carbs and 60 calories logged as roughly 7 grams of fat. The point is to account for the calories so they don’t sneak past your daily totals.
When to Adjust Your Targets
Your starting macro targets are an educated guess. Expect to refine them. Weigh yourself at the same time each day (morning, after using the bathroom) and track the weekly average. If your average weight isn’t moving in the direction you want after two to three consistent weeks, your calorie balance needs adjusting.
A plateau happens when the calories you eat match the calories you burn, and the deficit you started with no longer exists. As you lose weight, your body burns fewer calories at rest, and your non-exercise movement (steps, fidgeting, general activity) often drops without you noticing. One study-backed strategy is to monitor your daily step count and make sure it doesn’t decline as you diet. If it does, intentionally bring it back up.
When you hit a stall, you have a few options. You can reduce your calorie target by another 100 to 200 calories, primarily by trimming carbs or fat while keeping protein steady. You can increase your activity. Or you can take a “diet break,” eating at maintenance calories for a few days up to two weeks. This can improve adherence and help offset some of the metabolic slowdown that comes with prolonged dieting. After the break, return to your deficit.
Protein is the macro to protect during adjustments. If anything, increase it when you cut calories further. Keeping protein at 0.7 to 1.0 grams per pound of body weight becomes even more important as your deficit deepens, because the risk of losing muscle tissue alongside fat grows when calories are low.