Once you understand what macros are, the next question is the practical one: what should your numbers actually be? The answer is not one-size-fits-all — it depends on your goal and your bodyweight. But the method for finding your targets is straightforward, and you can have your numbers in about five minutes. Here's how.
What should my macros be?
Your macros depend on your goal and bodyweight. A common starting split is 30% protein, 40% carbs, and 30% fat. For fat loss or muscle gain, set protein first at 0.7–1 gram per pound of bodyweight, then divide your remaining calories between carbs and fat based on training and preference.
Notice the two approaches packed into that answer. Percentage splits are a quick starting point, but the more reliable method — especially if you train — is to set protein as a fixed amount first, then build the rest of your day around it.
Start with calories, then split into macros
Macros live inside a calorie target, so you need that number first. Estimate your maintenance calories (the amount that keeps your weight stable), then:
- For fat loss: subtract roughly 15–20% to create a moderate deficit.
- For muscle gain: add roughly 5–10% for a lean surplus.
- For body recomposition: stay at or just below maintenance with high protein. We cover this in depth in can you build muscle in a calorie deficit.
Once you have your daily calories, you split them into grams of protein, carbs, and fat.
The protein-first method
This is the approach most coaches use because it prioritizes the macro that matters most for body composition.
- Set protein. Multiply your bodyweight in pounds by 0.7 to 1. A 170-pound person lands at roughly 120–170 grams of protein. (For the full reasoning, see how much protein you need.)
- Set fat. Allocate about 0.3 to 0.5 grams of fat per pound of bodyweight — enough to support hormones. For a 170-pound person, that's roughly 50–85 grams.
- Fill the rest with carbs. Whatever calories remain after protein and fat go to carbohydrates. Carbs are your flexible fuel — they flex up on training days and down on rest days if you prefer.
A worked example
Let's run the numbers for a 170-pound person aiming for fat loss at 2,200 calories a day:
- Protein: 170 grams × 4 calories = 680 calories
- Fat: 65 grams × 9 calories = 585 calories
- Carbs: the remaining 935 calories ÷ 4 = about 235 grams
So the target is roughly 170g protein / 235g carbs / 65g fat. That's it — a complete, goal-aligned macro target built in three steps.
Common macro splits by goal
If you prefer percentage-based starting points, these are reasonable ranges:
- Fat loss: higher protein, moderate carbs, moderate fat (e.g., 35/35/30).
- Muscle gain: moderate protein, higher carbs to fuel training (e.g., 30/45/25).
- Maintenance / recomposition: balanced, protein-forward (e.g., 30/40/30).
Treat these as a launch point, not a rule. The protein-first method tends to produce better results because it anchors the most important macro instead of letting it float.
How and when to adjust
Your first targets are a hypothesis, not a verdict. Track them consistently for two to three weeks, watch your weekly weight trend and how you feel and perform, then adjust:
- Losing too fast or feeling drained? Add some carbs back.
- Not losing at all? Trim 100–150 calories, usually from carbs or fat.
- Strength dropping in the gym? Make sure protein is high enough and consider more carbs around training.
Small, patient adjustments beat dramatic overhauls every time.
Put your numbers to work
The best macro targets in the world do nothing if you don't track against them. Once you've calculated your protein, carb, and fat goals, plug them into your tracker and start logging — that's how targets turn into results. Our guide on how to track macros shows the easiest way to do it.
Set your macro targets in 21 Fitness and start tracking today — try it free. Enter your goals once, then log meals by voice and watch your daily totals line up against your numbers automatically.
Frequently asked questions
Should my macros change on rest days? They can. Some people lower carbs slightly on rest days and raise them on training days, keeping protein and weekly calories the same. It's optional — consistent daily targets work fine too.
How accurate do my macros need to be? Aim to land within about 5–10 grams of each target. Chasing exact numbers adds stress without meaningfully improving results.
Internal links: How to Track Macros · How Much Protein Do I Need? · Can You Build Muscle in a Calorie Deficit?
External sources: Dietary Guidelines for Americans (dietaryguidelines.gov) · International Society of Sports Nutrition (jissn.biomedcentral.com) · Examine.com