FitDexProtein intake calculator
Most protein calculators give you one number and stop: "this many grams a day". But how those grams are spread across the day matters as much as the total — muscle protein synthesis saturates per meal, and the part above the ceiling goes to energy rather than muscle. Enter your measurements and how many meals you eat, and we'll work out both the target and whether it fits into those meals.
Your daily protein target
range 148–180 g · 2.0 g/kg
| One meal's protein equals | Amount |
|---|---|
| Chicken breast — skinless, cooked | 176 g |
| Egg — boiled | 434 g · 8.7 eggs |
| Lentils — cooked | 607 g |
| Tofu | 675 g |
- Multiple of the reference intake (RDA)2.5×
- Per kilo of lean mass2.57 g/kg
- Share of your daily calories656 kcal · 28%
The hard part of hitting a protein target is not the arithmetic but knowing how much you actually got by the end of the day. FitDex shows protein as its own bar next to calories as you log each meal, so the days you fall short show up before the evening.
How do you spread protein across the day?
For most people the problem is distribution rather than the total: almost none in the morning, half the day's protein at dinner. Spreading the same total evenly across meals is easier than raising it and, in most cases, more effective. The steps below are what that looks like in practice.
- Start with breakfast. It is usually the weakest meal of the day and also the easiest to fix: eggs, cottage cheese or yoghurt on their own bring the meal close to the ceiling.
- Put a protein source on the plate first in every meal, then build the rest around it. When the plate is assembled the other way round, protein usually ends up squeezed into whatever space is left.
- If you use plant sources, factor in the volume: getting the same protein from lentils means a portion several times larger than from chicken. If a single meal becomes a struggle, adding a meal is the more realistic move.
- On training days, try adding a meal rather than raising the total. Because the saturation ceiling is fixed per kilo of body weight, the way to get value out of extra protein is to put it in a new meal.
- Measure against the target for a week before deciding anything. A single day's total sits inside normal fluctuation; changing the target before a trend is visible is an early intervention.
How is it calculated?
The calculation runs on body weight rather than calories: every published guideline states protein in grams per kilogram (g/kg). In the sample body, 82 kg × 2.0 = 164 grams. This can differ from the number on our macro calculator page, and that is expected — there protein is a percentage of calories, here it is a function of the body.
Where the range sits depends on training status and goal. The ISSN position stand (Jäger et al., 2017) gives 1.4–2.0 g/kg for gaining or maintaining muscle; in Morton et al.'s 2018 meta-analysis the extra benefit flattens out around 1.6 g/kg. In the sample body the range is 148–180 grams, with a recommended midpoint of 164.
LOSING WEIGHT RAISES THE REQUIREMENT, IT DOES NOT LOWER IT. Counter-intuitive. The reason is simple, though: in a calorie deficit the body has to cover the energy from somewhere, so it looks at the sources it has, and muscle tissue is one of them. Protein is the lever that pushes the loss towards fat. That is why the "lose weight" column of the grid sits above the "maintain" column.
The per-meal saturation ceiling is roughly 0.4 grams per kilo (Schoenfeld & Aragon, 2018 review). In the sample body, 82 × 0.4 = 33 grams. Splitting 164 grams a day across three meals gives 55 grams per meal — well above that ceiling; spreading the same total across five meals resolves it. That is why this page asks how many meals you eat.
The result is also shown per kilogram of LEAN MASS. Helms et al. (2014) recommend 2.3–3.1 g/kg of lean mass for lean athletes in a deficit; the sample body comes out at 2.57, inside that range. Two different routes landing in the same place is a second sign that the target is reasonable.
Over 65 the floor is raised. With age the same amount of protein triggers less muscle building — this is called anabolic resistance — and the PROT-AGE and ESPEN guidelines give 1.0–1.2 g/kg for this age group, or 1.2–1.5 g/kg for those who are active or unwell. Enter an age of 65 or above and the range no longer drops below that band.
How to read your result
Look at the range under the big number before the number itself. 164 grams is a midpoint; 148–180 is the band you should actually aim at. Closing one day at 152 and the next at 176 is not a deviation, it is staying inside the range. Aiming at a single figure manufactures a sense of failure on every day you miss it.
The per-meal box is this page's real message. In the sample body each meal carries 55 grams against a ceiling of 33; the 22 grams in between go to energy rather than muscle. The right response is not to raise the total but to spread the same total across more meals. The page tells you how many meals that takes.
The equivalence table turns abstract grams into a plate, and what it really teaches is the difference in volume. One meal's protein is 176 grams of chicken breast — or 607 grams of cooked lentils, or 675 grams of tofu. Same protein. Four times the plate. For someone eating plant-based, this is the point where adding meals stops being a preference and becomes a necessity.
The multiple of the reference intake is a scale, not a warning. In the sample body the target is 2.5× the reference intake of 66 grams. That reference is the floor that prevents deficiency; the guidelines themselves do not present it as optimal. A multiple between 2 and 3 is what you would expect for someone who trains; close to 1 means the target is merely out of deficiency territory, not dialled in.
The lean-mass line is a second check. In someone with a high body fat percentage, calculating per kilo of body weight overstates the requirement somewhat, because fat tissue demands far less protein than muscle. If the two numbers come out close, the target is safe; if the per-lean-kilo figure climbs above 3.1, dropping to the lower end of the range makes more sense.
The calorie share tells you whether the target is sustainable. In the sample body protein is 28% of daily calories, which leaves enough room for carbohydrate and fat. If that share goes above 35%, the amount of protein is not itself a problem, but the other two macros are being squeezed — either raise the calorie target or move protein to the lower end of the range.
Frequently asked questions
This page gives a different number from the macro calculator — which one is right?
Both are right; they answer different questions. The macro page divides your daily calories into three macros, so protein there depends on the calorie target: cut calories and protein falls with them. This page derives protein from body weight and raises the target in a deficit. If preserving muscle is the priority, take the number from here and distribute carbohydrate and fat across the calories that are left.
Does too much protein damage the kidneys?
In healthy adults without kidney disease there is no evidence that protein intake at the ranges on this page impairs kidney function; the concern largely comes from generalising the restriction advised for kidney patients to healthy people. If you have a known kidney condition, though, it is a different situation: there the amount of protein is for the doctor following you to set, not a web page.
If I go over the per-meal ceiling, is that protein completely wasted?
No — "wasted" is the wrong word. Protein above the ceiling does not stimulate more muscle building, but the body still uses it for other jobs and burns some as energy, and its effect on satiety continues. So someone eating two large meals is not starving; they are simply getting less muscle building out of the same total. Adding meals is the cost-free way to close that gap.
Is it possible to hit this target on a plant-based diet?
It is possible, but it takes planning, and the difficulty is volume rather than finding protein. The equivalence table shows it directly: one meal's protein is 176 grams of chicken breast but 607 grams of cooked lentils. The practical fix is usually to add meals and to lean on denser sources — tofu and tempeh over lentils, legume spreads, soy products. For amino acid coverage, combining legumes and grains across the day is enough; they do not have to be paired in every meal.
Related tools
- Macro calculatorTurn your daily calorie target into grams of protein, carbohydrate and fat. We publish the ratio we use and why we chose it, instead of offering preset templates with no explanation.
- Calorie calculatorEnter your height, weight, age and activity level to see your daily calorie needs, basal metabolic rate and macro split in seconds. The same formula as the FitDex app.
- Meal plate builderEnter a calorie target and a protein floor, get the grams for all four zones of the plate. It runs backwards: you give the total, the tool solves the grams. It also shows how much room is left for the grain when you change the protein source.
- Food swap calculatorWhat do you gain by replacing something you eat with a lighter alternative at the same weight? 80 foods, computed at your own portion. The difference: it marks the swaps that cut calories without cutting protein and fibre.
This tool is for information only and is not a substitute for medical diagnosis or treatment. Talk to a healthcare professional before making a lasting change to how you eat.