How to Calculate Macros for Cutting, Bulking, or Maintaining
To calculate macros, first find your daily calorie target, then split that number into protein, carbohydrate, and fat grams based on your goal. Protein is usually set first, around 0.7 to 1 gram per pound of bodyweight, fat is set next at roughly 20 to 30 percent of total calories, and carbohydrates fill whatever calories remain. The exact split shifts slightly depending on whether you are cutting, maintaining, or bulking.
Starting from your total calorie number
Macro math only works once you already know your daily calorie target, since protein, carbohydrate, and fat grams are simply pieces of that total. Each gram of protein and carbohydrate provides four calories, while each gram of fat provides nine calories. Once you know your total and your goal, the split becomes a straightforward calculation rather than a guess.
How to calculate macros step by step
Take a person with a maintenance calorie target of 2200 calories per day and a bodyweight of 170 pounds. Start with protein at 0.9 grams per pound, which gives 153 grams of protein, worth 612 calories. Next set fat at 25 percent of total calories, which is 550 calories, or about 61 grams of fat. Subtract both from the total: 2200 minus 612 minus 550 leaves 1038 calories for carbohydrates, which works out to about 260 grams of carbohydrate. That full split, roughly 153 grams protein, 61 grams fat, and 260 grams carbohydrate, is the maintenance target for this person.
Adjusting the same numbers for cutting and bulking
For a cut, the same person might drop total calories to 1800 while keeping protein high to protect muscle, since protein needs actually increase slightly as a percentage during a deficit. At 1 gram per pound, protein becomes 170 grams, worth 680 calories. Fat drops to about 20 percent of total, which is 360 calories or 40 grams. That leaves 760 calories for carbohydrate, roughly 190 grams. For a bulk, calories might rise to 2700, protein stays around 0.8 grams per pound at 136 grams, fat holds near 25 percent at 675 calories or 75 grams, leaving 1350 calories for carbohydrate, about 337 grams. Notice how protein stays relatively stable across all three goals while carbohydrate is the number that moves the most.
Macro splits at a glance
| Goal | Calories | Protein | Fat | Carbohydrate |
|---|---|---|---|---|
| Cutting | 1800 | 170g | 40g | 190g |
| Maintenance | 2200 | 153g | 61g | 260g |
| Bulking | 2700 | 136g | 75g | 337g |
A short checklist before you start tracking
- Confirm your total daily calorie target first, since every macro depends on it.
- Set protein based on bodyweight rather than a fixed percentage, so it stays consistent as calories change.
- Do not drop fat below roughly 15 percent of total calories, since hormone production needs a baseline amount.
- Let carbohydrate be the flexible number that absorbs whatever calories remain.
- Recheck your macros every few weeks as bodyweight or activity level shifts.
Getting comfortable with macros
Getting this right matters because small errors compound the longer they go unnoticed, and a quick sanity check now saves a bigger correction later. Write down the inputs and assumptions you used so you can compare results later and spot exactly what changed if the numbers look different next time. Treat any online tool as a way to confirm your own reasoning rather than a black box, since understanding the logic behind the number is what actually builds confidence. Real world data is rarely as clean as a textbook example, so expect to make small adjustments once you apply the same method to your own numbers. Keep the process simple and repeatable so you can run it again next month or next year without relearning the steps from scratch. A second pair of eyes, or a second tool, is a cheap way to catch a mistake before it turns into a bigger problem downstream. Most people get this wrong the first time not because the concept is hard, but because a small step gets skipped under time pressure.
Once the basic method clicks, the same logic tends to show up again in other parts of the same field, which makes the extra few minutes spent learning it worthwhile. Getting this right matters because small errors compound the longer they go unnoticed, and a quick sanity check now saves a bigger correction later. Write down the inputs and assumptions you used so you can compare results later and spot exactly what changed if the numbers look different next time. Treat any online tool as a way to confirm your own reasoning rather than a black box, since understanding the logic behind the number is what actually builds confidence. Real world data is rarely as clean as a textbook example, so expect to make small adjustments once you apply the same method to your own numbers.
Get your calorie target first
Before you can split any macros, you need an accurate calorie number. Use the TDEE and Calorie Calculator to find your daily energy needs based on your age, weight, activity level, and goal.
Open the TDEE CalculatorThen let the math run itself
Once you have a calorie target, the Macro Calculator converts it into exact protein, fat, and carbohydrate grams for cutting, maintenance, or bulking, so you skip the manual arithmetic entirely.
Open the Macro CalculatorRelated tools for finishing the job
Macros are one piece of a broader nutrition picture. Checking your BMI alongside your macro targets can give useful context, though body composition matters more than BMI alone. Hydration also plays a role in performance and recovery, so the Water Intake Calculator is worth pairing with your macro plan. For the complete set of nutrition and fitness tools, visit the health and fitness tools page, and read more nutrition breakdowns on the ConvertNow blog.
Key takeaway
Macros are just your calorie target divided into protein, fat, and carbohydrate grams based on your goal, and the split shifts more in carbohydrate than in protein as you move between cutting and bulking. Skip the manual math with the Macro Calculator once you know your daily calories.
FAQ: How to Calculate Macros
How to calculate macros if I already know my calorie target?
Set protein first based on bodyweight, set fat as a percentage of total calories, then let carbohydrate fill whatever calories remain after protein and fat are subtracted from the total.
How much protein do I need per day?
Most people aiming to build or preserve muscle should target roughly 0.7 to 1 gram of protein per pound of bodyweight per day.
Should protein change between cutting and bulking?
Protein often increases slightly as a percentage during a cut to help preserve muscle in a calorie deficit, while it can be slightly lower during a bulk since extra calories support muscle growth on their own.
What is the minimum amount of fat I should eat?
Most guidance suggests keeping fat above roughly 15 to 20 percent of total daily calories to support hormone production and overall health.
Why does carbohydrate change more than protein or fat?
Carbohydrate is typically treated as the flexible macro that absorbs whatever calories remain after protein and fat are set, so it naturally shifts the most as total calories rise or fall.
Do I need to track macros exactly every day?
Exact daily precision is not required for most people; staying within a reasonable range of your targets most days will still produce results over time.
How many calories are in a gram of protein, carbohydrate, and fat?
Protein and carbohydrate each provide four calories per gram, while fat provides nine calories per gram.
Can I use a general macro ratio instead of doing the math myself?
General ratios can work as a starting point, but calculating macros from your own bodyweight and calorie target gives a more accurate and personalized result than a generic percentage split.