How do I calculate my macros?

Three steps: find your daily calorie target from your TDEE, set protein at 1.6-2.2 g/kg bodyweight, set fat at 0.5-1 g/kg, then fill the remaining calories with carbohydrate. Convert grams to calories with the 4-4-9 rule.

What is the 4-4-9 rule for macros?

It's the calorie value of each macro: protein and carbohydrate are 4 calories per gram, fat is 9. Multiply your gram targets by these to check they sum to your calorie goal.

What macro split is best for weight loss?

Protein should stay high to preserve muscle (1.6-2.2 g/kg). Beyond that, the carb-to-fat split is largely personal preference — research shows similar fat loss across ratios when protein and calories are matched. Choose the split you can stick to.

How to Calculate Your Macros (Step by Step)

Calculating your macros means turning a daily calorie target into grams of protein, carbohydrate, and fat. It sounds technical, but it’s three steps and a multiplication rule. Get protein right and the rest is flexible.

Step 1: Set your calories

Macros live inside a calorie budget, so find that first. Calculate your TDEE (maintenance), then adjust for your goal — minus 300-500 for fat loss, plus 150-300 for lean gain. The TDEE calculator gives you the number. Say your target is 2,000 calories/day.

Step 2: Set protein and fat first

Protein and fat have floors backed by evidence; carbs fill the rest.

Protein: 1.6-2.2 g/kg bodyweight (Morton et al., 2018 meta-analysis). For a 70 kg person at 1.8 g/kg: 126 g protein. Lock this in with the protein calculator — it’s the macro that protects muscle in a deficit and drives satiety.
Fat: 0.5-1 g/kg. For 70 kg at 0.8 g/kg: 56 g fat. Going much lower can impair hormone production.

Step 3: Fill the rest with carbs using the 4-4-9 rule

Each macro has a fixed calorie value — the 4-4-9 rule:

Protein: 4 cal/g → 126 g × 4 = 504 cal
Fat: 9 cal/g → 56 g × 9 = 504 cal
Remaining for carbs: 2,000 − 504 − 504 = 992 cal → ÷ 4 = 248 g carbs

Final macros: 126 g protein, 56 g fat, 248 g carbs. They sum back to 2,000 calories — always check that they do.

Adjusting the split

Once protein is set, the carb/fat balance is mostly preference. Endurance athletes lean higher-carb; some people feel better higher-fat. The DIETFITS trial (JAMA 2018) found similar fat loss across splits when protein and calories matched — so pick the ratio you can actually sustain.

The hard part isn’t the math

Calculating macros takes five minutes. Hitting them daily is the real work, and it depends on accurately knowing what’s on your plate — where portion misjudgment quietly wrecks the numbers. Whether you log by database or by photographing the meal, the calculation only pays off if the daily tracking is accurate. Recalculate your macros after a 5%+ change in bodyweight or a shift in goal.

Frequently asked questions

How do I calculate my macros?: Three steps: find your daily calorie target from your TDEE, set protein at 1.6-2.2 g/kg bodyweight, set fat at 0.5-1 g/kg, then fill the remaining calories with carbohydrate. Convert grams to calories with the 4-4-9 rule.
What is the 4-4-9 rule for macros?: It's the calorie value of each macro: protein and carbohydrate are 4 calories per gram, fat is 9. Multiply your gram targets by these to check they sum to your calorie goal.
What macro split is best for weight loss?: Protein should stay high to preserve muscle (1.6-2.2 g/kg). Beyond that, the carb-to-fat split is largely personal preference — research shows similar fat loss across ratios when protein and calories are matched. Choose the split you can stick to.