Rex says
Same equations the textbooks use — just way less awkward. Pop in your stats and I'll tell you what the number actually means for you.
Try a scenario
Click to load — tweak from there.Inputs
Result
Protein per day (g)
180
Carbs per day (g)
240
Fat per day (g)
80
Protein per meal (g)
45
Carbs per meal (g)
60
Fat per meal (g)
20
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter daily calories.
- 2Enter split.
- 3Enter meals per day.
- 4Read your protein per day (g) on the right — it updates as you type.
- 5Hit Share to keep the scenario or send it to someone.
About this calculator
Set protein first from body weight, fat second for hormone health at 20–30% of calories, and let carbohydrate fill the rest — that ordering matters more than the exact ratio.
Worked example
Using the values the calculator loads with:
Inputs
- Daily calories: 2400
- Split: Balanced 30/40/30
- Meals per day: 4
Results
- Protein per day (g): 180
- Carbs per day (g): 240
- Fat per day (g): 80
- Protein per meal (g): 45
- Carbs per meal (g): 60
- Fat per meal (g): 20
What each field means
Inputs
- Daily calories
- The daily calories used in the calculation. Starts at 2400 so you have a working example on load. Accepted range: 1000–6000.
- Split
- Pick the option that matches your situation — the maths changes per option. Choices: Balanced 30/40/30, High protein 40/35/25, Low carb 35/20/45, Endurance 25/55/20, Keto 25/5/70.
- Meals per day
- The meals per day used in the calculation. Starts at 4 so you have a working example on load. Accepted range: 1–8.
Results
- Protein per day (g)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Carbs per day (g)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Fat per day (g)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Protein per meal (g)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Carbs per meal (g)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Fat per meal (g)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the macronutrient split calculator work?
Set protein first from body weight, fat second for hormone health at 20–30% of calories, and let carbohydrate fill the rest — that ordering matters more than the exact ratio. The underlying maths is: Protein and carbs at 4 cal/g, fat at 9 cal/g, summing to your calorie target.
What do I need to enter?
3 values: daily calories, split, and meals per day. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the protein per day (g) result mean?
It is returned as a decimal number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
Who is this tool for?
It's built for anyone tracking a health or training target and wanting the standard formula applied correctly, without a signup or an app.
Accuracy and limitations
- Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
- Results do not account for medical conditions, medication, or pregnancy.
- Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Macro Split Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/macro-split
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/macro-split" target="_blank" rel="noopener">Macro Split Calculator — RevenueLab</a> (2026).</p>
Source: [Macro Split Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/macro-split) (2026).