Counting macros means tracking the three main nutrients in your food: protein, carbohydrates, and fat. Each one provides a different amount of energy. Protein and carbohydrates each supply 4 calories per gram, while fat supplies 9 calories per gram. The process involves setting a calorie target, splitting those calories into macro percentages, then logging your food to hit those numbers each day.
Step 1: Find Your Calorie Target
Before you can divide calories into macros, you need to know how many calories your body uses in a day. This is called your Total Daily Energy Expenditure, or TDEE, and it combines two things: your baseline metabolism (the calories you burn just being alive) and your activity level.
Your baseline metabolism is calculated using your weight, height, age, and sex. The most widely used formula, the Harris-Benedict equation, works like this:
- Males: 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) − (5.677 × age in years)
- Females: 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) − (4.330 × age in years)
To convert pounds to kilograms, divide by 2.2. To convert inches to centimeters, multiply by 2.54. A 30-year-old woman who weighs 150 pounds (68 kg) and stands 5’6″ (168 cm) would get a baseline of roughly 1,440 calories per day.
Next, multiply that number by an activity factor to account for how much you move. The Food and Agriculture Organization classifies these into three tiers: sedentary or light activity (multiply by 1.4 to 1.69), moderately active (1.7 to 1.99), and vigorously active (2.0 to 2.4). Most people with desk jobs who exercise a few times per week fall somewhere in the 1.5 to 1.7 range. Using our example above, that 30-year-old woman with a moderate exercise routine might multiply 1,440 by 1.6, landing at roughly 2,300 calories per day.
If your goal is fat loss, you’d subtract 300 to 500 calories from that number. For muscle gain, you’d add 200 to 300. For maintenance, use the number as is.
Step 2: Set Your Macro Split
The Dietary Guidelines for Americans recommend these ranges for adults: 45 to 65 percent of calories from carbohydrates, 20 to 35 percent from fat, and 10 to 35 percent from protein. Those ranges are wide on purpose. Where you land within them depends on your goals and preferences.
A common starting point for someone who exercises regularly is 40% carbs, 30% protein, and 30% fat. Someone focused on building muscle might push protein higher (closer to 35%) and lower carbs slightly. Someone training for endurance events often benefits from keeping carbs on the higher end. There’s no single “correct” split, but staying within the recommended ranges ensures you’re getting enough of each nutrient to support basic health.
Step 3: Convert Percentages to Grams
This is where the math comes together. Take your calorie target, apply each percentage, then divide by the calories per gram for that nutrient. Here’s a worked example using a 2,000-calorie target with a 40/30/30 split:
- Carbs (40%): 2,000 × 0.40 = 800 calories ÷ 4 = 200 grams
- Protein (30%): 2,000 × 0.30 = 600 calories ÷ 4 = 150 grams
- Fat (30%): 2,000 × 0.30 = 600 calories ÷ 9 = 67 grams
Those gram targets are what you track throughout the day. Most people find it easier to prioritize hitting protein first, since it tends to be the hardest macro to reach, then fill in carbs and fat around it.
A Note on Protein Targets
The official Recommended Dietary Allowance for protein is 0.8 grams per kilogram of body weight (about 0.36 grams per pound). That’s the minimum to prevent deficiency, not necessarily the amount that’s optimal for someone who lifts weights or exercises regularly. Many people who count macros aim for 1.6 to 2.2 grams per kilogram, which is a range commonly used in fitness and sports nutrition. For a 150-pound person, that works out to roughly 109 to 150 grams of protein per day.
Step 4: Track Your Food
Every packaged food has three key lines on its Nutrition Facts label: Total Fat, Total Carbohydrate, and Protein. These are your macro numbers. The critical detail most people miss is serving size. All the values on the label refer to one serving, so if a package contains three servings and you eat the whole thing, you multiply every number by three.
For foods without labels (fresh meat, produce, grains), apps like MyFitnessPal, Cronometer, or MacroFactor pull from food databases that list macros per weight or common serving size. You log what you eat, the app tallies your running totals, and you adjust the rest of your meals to stay near your targets.
Weighing vs. Measuring Cups
A digital kitchen scale is the single most useful tool for counting macros accurately. Weighing food by grams or ounces is consistently more accurate than scooping with measuring cups, because volume measurements depend on the size and shape of the food. A cup of diced chicken breast can vary significantly depending on how tightly you pack it or how large the pieces are.
Even small discrepancies add up. Just 25 extra grams of tomato, an amount you’d barely notice in a measuring cup, adds meaningful calories over the course of a day when it happens across multiple ingredients. If you’re casually tracking, measuring cups work fine. If you’re tracking to hit specific targets for a body composition goal, a scale costing $10 to $15 will make the biggest difference in accuracy.
Tracking Net Carbs
Some people, particularly those on lower-carb approaches, track net carbs instead of total carbs. Net carbs attempt to capture only the carbohydrates your body fully absorbs. The calculation varies depending on the type of carb:
Fiber passes through your digestive system largely undigested, so you subtract all fiber grams from total carbohydrates. Sugar alcohols (found in many protein bars and sugar-free products) are partially absorbed. The standard approach, recommended by UCSF’s Diabetes Teaching Center, is to subtract half the sugar alcohol grams from total carbohydrates. For example, a bar with 29 grams of total carbs and 18 grams of sugar alcohols would count as 20 net carbs: 29 minus 9 (half of 18) equals 20.
How to Handle Alcohol
Alcohol contains 7 calories per gram, but it doesn’t appear as its own line on most tracking apps. The workaround is to convert alcohol calories into one of your existing macros. To count a drink as carbs, divide the total calories in the drink by 4. To count it as fat, divide by 9. A 150-calorie glass of wine would count as either 37.5 grams of carbs or about 17 grams of fat. Some people split the difference and borrow from both their carb and fat budgets.
Keep in mind that many alcoholic drinks already contain actual carbohydrates (beer, cocktails with mixers), which will be listed in any food database. The conversion method above is specifically for the alcohol calories themselves, the portion that doesn’t fit neatly into the three standard macros.
Practical Tips for Consistency
You don’t need to hit your macro targets to the gram. Staying within 5 to 10 grams of each target on most days is realistic and effective. Perfection over a single day matters far less than consistency over weeks.
Meal prepping helps enormously because you calculate macros once and then eat the same portions multiple times. If cooking in bulk, weigh the total batch, log the total macros, then divide by the number of portions. Many tracking apps have a “recipe” feature that does this automatically.
Eating out is trickier, but most chain restaurants publish nutrition information online. For independent restaurants, estimate by logging the individual components: a piece of grilled fish, a cup of rice, a tablespoon of oil. You won’t be exact, and that’s fine. The goal is a reasonable estimate, not a laboratory measurement. Over time, you develop an intuitive sense of portion sizes and macro density that makes the whole process faster and less dependent on constant logging.