Protein calculator
Enter your weight, how hard you train and what you're trying to do. You'll get a daily protein target in grams, a sensible amount per meal, and an explanation of where the number came from.
Calculate your daily protein target
Your daily target
g of protein a day
Aim for about g on a typical day.
Now the hard part: actually hitting it
Knowing your number takes two minutes. Hitting it takes a habit. PRO.TEIN tracks that one number and turns each day into a square on a calendar — so a week of guessing becomes a week you can actually see.
How this calculator works
There is no clever formula here, and you should be suspicious of any protein calculator that implies otherwise. Daily protein requirements scale with body weight, and everything else — training, age, whether you're in a calorie deficit — moves the multiplier up or down. That's the whole model.
The calculator multiplies your body weight in kilograms by a grams-per-kilogram range drawn from published position stands, then adjusts it for age and for whether you're dieting. The ranges are these:
| Who | g per kg per day | 75 kg person |
|---|---|---|
| Sedentary adult, no particular goal | 0.8–1.0 | 60–75 g |
| Lightly active | 1.0–1.4 | 75–105 g |
| Training regularly, building or keeping muscle | 1.4–2.0 | 105–150 g |
| Training hard, actively building muscle | 1.6–2.2 | 120–165 g |
| Training twice daily or competing | 1.7–2.2 (to 2.4 when building) | 128–165 g |
| Losing fat, trying to keep muscle | 1.8–2.4 | 135–180 g |
| Healthy adult over 65 | 1.0–1.2 (1.2–1.5 if active) | 75–90 g |
Why the answer is a range, not a single number. The research doesn't support a precise figure, so a calculator that hands you "142 g" is manufacturing confidence it hasn't earned. Anywhere in your range is fine. Consistency across a week matters far more than precision on any one day.
Why weight, and not calories?
You'll see protein prescribed as a percentage of calories — "30% of your intake" — and it's a worse method. It ties your protein to how much you happen to be eating, which means the day you eat less, you also get less protein. That's precisely backwards: on a diet, when calories fall, protein needs go up, not down.
Anchoring to body weight avoids that entirely. Your requirement is a property of your body, not of your appetite.
When to use an adjusted weight
Protein requirements track lean mass. Body fat is metabolically cheap to maintain, so if you're carrying a substantial amount of it, calculating from total body weight inflates the target — sometimes to a figure that's genuinely hard to eat.
If you enter your height and your BMI comes out above 30, the calculator quietly switches to an adjusted body weight: the weight at a BMI of 25, plus a quarter of the excess. It's a rough correction, but it's much closer than using the raw number. If you leave height blank, it uses your body weight as entered and says so.
Splitting it across the day
Total daily protein is the thing that matters most, and by a wide margin. But distribution is a cheap second-order win: muscle protein synthesis responds to a per-meal dose of roughly 0.4 g per kilogram of body weight, and plateaus after that. Three or four meals of that size covers a typical daily target comfortably.
For a 75 kg person that's around 30 g per meal — a chicken breast, a large pot of Greek yoghurt with a scoop of whey, or a tin of tuna and two eggs. Practically, this is why one enormous protein-heavy dinner is a slightly less efficient way to eat 150 g than three moderate meals.
Don't let the per-meal number become a rule. If the choice is between hitting 150 g across two meals and hitting 110 g across four, take the 150. The daily total is the part with the strongest evidence behind it.
Is more always better?
No — the curve flattens. In a 2018 meta-analysis of 49 studies, Morton and colleagues found the benefit of additional protein for muscle gain plateaued at about 1.6 g/kg per day, with the confidence interval stretching to 2.2. Above that, extra protein isn't harmful, it just stops buying you more muscle. It's still useful for satiety, which is why the fat-loss range sits higher.
On safety: in healthy adults with normal kidney function, controlled trials at intakes well above these ranges haven't shown the kidney or bone problems that popular worry suggests. The 2018 review by Devries and colleagues is the usual reference. People with existing kidney or liver disease are a real exception, and that's a conversation for a doctor rather than a calculator.
Common questions
How much protein do I need per day?
For a sedentary adult, roughly 0.8–1.0 g per kilogram of body weight. For someone training regularly and wanting to build or keep muscle, 1.4–2.0 g/kg. For someone losing fat while trying to hold on to muscle, 1.6–2.4 g/kg. A 75 kg person who lifts a few times a week lands around 105–150 g per day.
Should the protein calculator use my current weight or my goal weight?
Protein requirements track lean mass, not total mass, and body fat needs very little protein to maintain. If you are carrying a lot of excess fat, calculating from your current weight will overshoot. This calculator switches to an adjusted body weight when your height and weight put you well above a healthy BMI.
Is there such a thing as too much protein?
For healthy adults with normal kidney function, controlled trials at intakes well above 2 g/kg have not shown harm to kidney or bone health. The practical ceiling is usually appetite and cost rather than safety. People with existing kidney or liver disease are a genuine exception and should be guided by their doctor.
How much protein can the body absorb in one meal?
Effectively all of it — absorption is not the bottleneck. The relevant question is how much stimulates muscle protein synthesis, which plateaus around 0.4 g per kilogram of body weight per meal for most people. Beyond that the extra protein is still used, just not for building muscle.
Do older adults need more protein?
Yes. Muscle becomes less responsive to protein with age, a phenomenon called anabolic resistance. The PROT-AGE and ESPEN expert groups recommend 1.0–1.2 g/kg for healthy older adults, and 1.2–1.5 g/kg for those who are active or recovering from illness.
Where these numbers come from
The ranges above are drawn from the International Society of Sports Nutrition position stand on protein and exercise (1.4–2.0 g/kg for active individuals); Morton and colleagues' 2018 meta-analysis in the British Journal of Sports Medicine (the ~1.6 g/kg plateau); Helms and colleagues' work on protein during energy restriction in lean athletes (the higher fat-loss figures); and the PROT-AGE and ESPEN expert group recommendations for older adults (1.0–1.2 g/kg, higher when active or ill). The 0.8 g/kg reference figure is the US RDA; the European Food Safety Authority uses 0.83 g/kg.
These are consensus ranges from position stands and meta-analyses rather than single studies, which is deliberate — individual protein studies are small and contradict each other regularly.
This is general information, not medical advice. A calculator can't account for your circumstances. If you have kidney or liver disease, diabetes, are pregnant or breastfeeding, or are managing any medical condition, your protein needs may differ substantially — speak to a doctor or registered dietitian before changing your diet.