Which split style should I choose?

Balanced suits general health goals, higher-protein is common for muscle-focused goals, and lower-carb suits people managing carb intake specifically — there's no single correct split for everyone.

Do these grams need to be hit exactly every day?

No — they're a target to aim for on average. Day-to-day variation is normal and expected.

Where do the 4 and 9 calories-per-gram figures come from?

They're the FDA's general Atwater conversion factors, used on nutrition labels in the United States — protein and carbohydrate each provide about 4 kcal/g, fat about 9 kcal/g.

Are these percentage splits official dietary guidelines?

They're common, reasonable presets that fall within the Acceptable Macronutrient Distribution Range (AMDR) — an accepted range, not a single mandated number — so slightly different splits can be just as valid depending on your goals.

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Health & Fitness

Macro Calculator

Protein, carb, and fat targets from a calorie goal.

🔒 Runs entirely in your browser — nothing here is ever uploaded

About the Macro Calculator

Splits a daily calorie target into grams of protein, carbohydrate, and fat based on a chosen split style, using standard calorie values for each macronutrient.

How to use it

Enter your Daily calories target — from the Calorie Calculator, or your own estimate.
Choose a Split style: Balanced, Low-carb, or High-protein.
Read your protein, carb, and fat targets in grams from the result panel and chart.

Formula

Protein grams = (calories × protein %) ÷ 4
Carb grams = (calories × carb %) ÷ 4
Fat grams = (calories × fat %) ÷ 9

The 4 / 4 / 9 calories-per-gram figures are the FDA's general Atwater conversion factors for protein, carbohydrate, and fat. The Balanced/Low-carb/High-protein percentage splits are editorial presets, not a single official prescription — each falls within the Acceptable Macronutrient Distribution Range (AMDR) published by the (U.S.) National Academies: 10–35% protein, 45–65% carbohydrate, 20–35% fat.

Worked example

2,200 calories on a balanced 30/40/30 split works out to roughly 165g protein, 220g carbs, and 73g fat per day.

Recommendations

• Protein needs often stay fairly constant across cutting and bulking phases — many people fix protein first and adjust carbs and fat around it.
• Fat carries more than double the calories per gram of protein or carbs, so small percentage changes there move the gram target a lot.
• Treat this as a starting point and adjust based on how your body responds over a few weeks, not a fixed prescription.

Frequently asked questions

These are the standard, well-established energy values for each macronutrient (sometimes called Atwater values) — fat is simply more energy-dense per gram than protein or carbohydrate.

Related tools

Calorie Calculator

TDEE Calculator

Ideal Weight Calculator

Sources

Cornell LII — 21 CFR § 101.9, Nutrition labeling of food (general Atwater calorie factors) — accessed 2026-08-19
National Academies — Rethinking the Acceptable Macronutrient Distribution Range for the 21st Century — accessed 2026-08-19

Disclaimer

Educational estimate, not medical advice. Consult a qualified clinician before making health decisions.