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
Daily protein target
158
Grams per meal
39
Calories from protein
630
Alternative target from lean mass
158
Minimum RDA
63
Equivalent ounces of protein
5.6
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter body weight (lb).
- 2Enter goal.
- 3Enter meals per day.
- 4Enter body fat (%).
- 5Read your daily protein target on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
The RDA of 0.36 g/lb prevents deficiency; it does not maximize muscle retention. Research on resistance-trained lifters clusters around 0.7–1.0 g per pound of body weight.
Worked example
Using the values the calculator loads with:
Inputs
- Body weight: 175 lb
- Goal: Build muscle
- Meals per day: 4
- Body fat: 18 %
Results
- Daily protein target: 158
- Grams per meal: 39
- Calories from protein: 630
- Alternative target from lean mass: 158
- Minimum RDA: 63
- Equivalent ounces of protein: 5.6
What each field means
Inputs
- Body weight (lb)
- The body weight used in the calculation, measured in lb. Starts at 175 lb so you have a working example on load. Accepted range: 60–500 lb.
- Goal
- Pick the option that matches your situation — the maths changes per option. Choices: Maintain, Build muscle, Cut / preserve muscle, Sedentary baseline.
- 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.
- Body fat (%)
- The body fat used in the calculation, measured in %. Starts at 18 % so you have a working example on load. Accepted range: 3–60 %.
Results
- Daily protein target
- 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.
- Grams per meal
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Calories from protein
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Alternative target from lean mass
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Minimum RDA
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Equivalent ounces of protein
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the daily protein intake calculator work?
The RDA of 0.36 g/lb prevents deficiency; it does not maximize muscle retention. Research on resistance-trained lifters clusters around 0.7–1.0 g per pound of body weight. The underlying maths is: Protein (g) = Body weight (lb) × goal multiplier.
What do I need to enter?
4 values: body weight, goal, meals per day, and body fat. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the daily protein target 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). Protein Intake Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/protein-intake
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/protein-intake" target="_blank" rel="noopener">Protein Intake Calculator — RevenueLab</a> (2026).</p>
Source: [Protein Intake Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/protein-intake) (2026).