Why this page never asks for a calorie target
A macro calculator starts from calories and slices them three ways, protein, carbohydrate and fat, so the protein figure it hands back moves whenever the calorie target does. This page works the other way round: protein in grams, set directly from your weight and your goal, with no calorie number sitting underneath it to shift the answer. Cutting, bulking or maintaining, the grams here stay put unless your weight or your goal changes. If you want the full three-way split against a calorie target instead, the Macro Calculator is the page built for that job.
That independence matters because protein need is driven mostly by body size and what your muscles are being asked to do, not by how many calories you happen to be eating that week. Someone cutting hard and someone bulking can share the same bodyweight and the same training goal, and the research points to a similar gram target for both of them, even though their calorie totals are miles apart.
The five bands, printed in full
Every band here is a range rather than a single number on purpose. Published protein research reports its findings as a band because individual response varies with training history, age and how much muscle a person is carrying, and printing a single decimal in its place would claim a precision the underlying studies do not have. The low end of each band is a safe, evidence-backed floor; the high end is the point past which extra protein has not been shown to add much further benefit for that particular goal.
The RDA of 0.8 g/kg is the odd one out: it is a minimum set to prevent deficiency in the general population, not a wellness target, which is why even the sedentary band nudges a little above it. Reanalyses of the same nitrogen-balance data using newer statistical methods have argued the true requirement sits closer to 1.0 to 1.2 g/kg for most healthy adults, which is why this page's sedentary band runs to 1.0 rather than stopping dead at 0.8.
Why the cutting band asks about body fat
The "losing weight, keeping muscle" band is published differently to the other four: as grams per kilogram of lean mass, not total bodyweight. That is deliberate. The research behind it comes from resistance-trained people in a calorie deficit, where the whole point of the higher protein target is to protect the lean tissue that is actually doing the training, so scaling it to lean mass rather than total weight is the more faithful reading of the studies it came from.
Without a body fat percentage, this page applies that band to your total weight instead, as a working approximation. That runs high for anyone carrying more body fat than average, since a chunk of their total weight is fat mass that the band was never meant to cover. Enter a body fat percentage, from callipers, a scan or the Body Fat Calculator, and the page switches this one band to lean mass directly; the other four bands stay on total weight regardless, since that is how their own research reports them.
Reading a range instead of a single number
Aim to land inside the band rather than chasing either edge of it. The low end suits someone newer to training, older, or simply happier eating less protein and more of something else; the high end suits someone leaner, further into a hard cut, or who trains often enough that recovery is the limiting factor. Sitting in the middle of the band is a reasonable default when neither edge obviously fits your situation better.
The per-meal table below splits that same range across three, four or five meals, so you can see roughly what a single plate needs to carry rather than only the full day's total. Splitting evenly is a simplification, real days rarely divide protein perfectly evenly, but it is a fair starting point for planning meals rather than trying to hit the number retrospectively at 9pm.
Is there a limit to how much helps in one sitting
Muscle-building research on single meals suggests the muscle-repair response to a dose of protein levels off somewhere around 0.4 g per kilogram of bodyweight in one sitting, roughly 25 to 40 g for most adults; protein beyond that in a single meal is increasingly used for energy or other purposes rather than building tissue in that meal specifically. That is a per-meal ceiling on the most efficient single dose, not a reason to eat less overall: a day's total still matters for reaching the ranges above, and spreading a high target across more, smaller meals is usually simpler than trying to push far past that per-meal figure in fewer sittings.
Reading the food-equivalents table
The table lower on this page turns your range into ordinary food rather than an abstract number: how many chicken breasts, eggs, or scoops of whey it would take to reach your low and high targets on their own. Nobody eats a single food all day, so treat it as a sense check for planning a plate, not a meal plan to follow literally; a real day mixes several of these sources rather than leaning on just one.
Questions people ask
How much protein do I need to build muscle?
Somewhere between 1.6 and 2.2 g per kilogram of bodyweight a day for most people resistance training with muscle gain as the goal. Below roughly 1.6 g/kg, more protein still helps; above about 2.2 g/kg, the evidence for extra benefit runs thin, so the top of the band is a reasonable ceiling rather than a floor to clear.
Is high protein bad for my kidneys?
Not for anyone with healthy kidneys. The caution around high protein and kidney health comes from advice given to people who already have kidney disease, where a lower intake helps slow its progression; it does not transfer to healthy adults, and controlled studies on higher protein intakes in healthy people have not found kidney harm. Anyone with an existing kidney condition should agree a protein target with a doctor rather than a calculator.
Why does the cutting band want my body fat percentage?
Because that particular band is published per kilogram of lean mass, not total weight. Skip it and the page applies the band to your total weight as an approximation, which sits a little high if you carry more body fat than average; add a body fat reading and the range narrows to your actual lean mass instead.
What if I am well below or above every band here?
Being a little under is rarely an emergency for one day, and being over is not harmful for anyone with healthy kidneys; consistency across most days matters far more than hitting an exact figure on any single one. If you are consistently well outside every band and unsure why, that is a reasonable moment to check in with a doctor or dietitian instead of adjusting the slider further.
Does this replace the Macro Calculator?
No, they answer different questions. This page works out protein on its own, independent of any calorie target. The Macro Calculator takes a calorie budget and splits it three ways, protein, carbohydrate and fat, so use that one once you already know how many calories you are eating and want the full breakdown.
Do older adults need more protein?
Often yes. Ageing muscle responds less efficiently to a given dose of protein, so several geriatric-nutrition reviews recommend healthy older adults aim for at least 1.0 to 1.2 g/kg a day, higher again for those managing illness, rather than settling for the plain RDA figure aimed at the general population.
Why is my target a range instead of one number?
Because the studies behind every band here report a range, not a single decimal. A calculator that turns that into one exact-looking number is claiming more precision than the underlying research supports; the range is the honest answer, and where you sit inside it is a reasonable personal call rather than something a formula can pin down for you.
This tool applies published population-level protein ranges to your weight and goal; it is not medical or dietetic advice. Anyone with kidney disease, another metabolic condition, or who is pregnant or breastfeeding should get a personal protein target from a doctor or registered dietitian rather than a calculator.