Protein needs are not one number — they depend on what you are asking your body to do. This calculator turns your weight and goal into a daily gram target using the grams-per-kilo ranges that sports-nutrition research actually supports, and splits it into a per-meal figure you can plan around.
Ranges follow the position stands and reviews on our methodology page. The 0.8 g/kg RDA is a minimum for sedentary adults, not an optimum.
The ranges, and where they come from
| Goal | Protein per kg body weight |
|---|---|
| Build muscle | 1.6 – 2.2 g |
| Lose fat, keep muscle | 1.8 – 2.4 g |
| Endurance sport | 1.2 – 1.6 g |
| Maintain / general health (active adults) | 1.2 – 1.6 g |
Two honest reference points. First, the RDA of 0.8 g/kg you will see quoted everywhere is a minimum — the amount set to prevent deficiency in sedentary adults — not an optimum for anyone who trains or diets. Second, more is not endlessly better: reviews of the research consistently find muscle-building benefits level off around 1.6–2.2 g/kg, which is why the ranges above have ceilings as well as floors.
Why is the fat-loss range the highest? In a calorie deficit your body is tempted to burn muscle along with fat; higher protein is the simplest lever that pushes back, and it is also the most filling macronutrient — useful when calories are tight.
Hitting the target without living on shakes
For an 80 kg adult on the maintain range, the target is 96–128 g a day. In food terms: 100 g of chicken breast gives roughly 31 g, two eggs about 12 g, a 170 g pot of Greek yogurt about 17 g, a scoop of whey about 24 g. Two protein-anchored meals plus a snack usually lands the day without any supplement at all. Our guide How Much Protein Do You Really Need? works through full sample days for each goal.
Protein questions
Should I count protein per meal? Total daily intake matters most. Splitting it across meals — the calculator shows a per-meal figure over three meals — simply makes the target easier to hit and digest.
Is a high-protein diet hard on healthy kidneys? In healthy adults, studies at these intakes have not shown kidney harm. If you have kidney disease or any medical condition, though, this calculator is not for you — your clinician’s number wins.
I’m vegetarian — do the ranges change? The gram targets stay the same; hitting them takes a little more planning (dairy, eggs, soy, lentils and combining grains with legumes across the day).