Choosing a Macro Split

Once you have a calorie target, you have to divide it. The four presets on our Macro Split Calculator cover the common approaches — here is what each one is actually for.

The presets at 2,000 kcal

What each suits

Balanced (30/40/30) — a reasonable default when you have no strong reason to skew. Moderate everything, no macro pushed to an extreme.

High protein (40/35/25) — useful when you are in a calorie deficit or training for muscle. Higher protein helps preserve lean mass while dieting and is the most satiating macronutrient, which makes a deficit easier to hold.

Low carb (40/20/40) — suits people who genuinely feel better eating this way. Note it is a substantial departure from official guidance and tends to be harder to sustain alongside high-volume endurance training, which leans on carbohydrate.

High carb (25/55/20) — sensible for endurance athletes and high training volumes, and it is the only preset that sits entirely within the official IOM ranges. See macro splits vs official guidelines.

The order of importance

Worth being blunt about the hierarchy, because macro splits attract more attention than they deserve:

1. Total calories decide whether you gain, lose, or maintain. This is the big one — get it from the TDEE Calculator.
2. Protein is the macro with the clearest evidence for a specific target, particularly when dieting or training. The Protein Intake Calculator sets it from body weight rather than as a percentage.
3. The carb/fat division is largely preference. Within sensible bounds, splitting the remainder differently matters far less than the two points above.

Someone hitting their calories and protein with a "wrong" carb/fat split will do better than someone with a perfect split who is not tracking calories.

Set protein first, then divide

A practical approach that avoids the main weakness of percentage-based splits:

1. Set your protein target from body weight using the Protein Intake Calculator — this is more direct than a percentage, since protein needs track your body, not your calorie total.
2. Check which preset lands nearest that number at your calorie level.
3. Divide the rest between carbs and fat by preference and training type.

This matters most at very low or very high calorie targets, where a fixed percentage can produce a protein figure well off what your body weight suggests.

Adjust from experience

No preset is a commitment. If you are constantly hungry, more protein or fat may help. If your training feels flat, carbs are the usual suspect. If a split feels sustainable and results are moving in the right direction, it is working — regardless of what it is called.

The bottom line

Use Balanced as a default, High protein when dieting or building, High carb for endurance work, and Low carb if it genuinely suits you. Then remember the hierarchy: calories first, protein second, and the carb/fat split a distant third. Run the numbers on the Macro Split Calculator.