How Much Protein Do You Really Need Per Day?
Last updated July 15, 2026
Protein is the one macronutrient almost everyone underthinks. The right amount depends on your body weight and how active you are — and the number that keeps you alive is very different from the number that helps you build or keep muscle. This guide walks through both, with the ranges that published research actually supports.
The RDA is a floor, not a target
The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight per day. It is important to understand what that number is: it is the minimum estimated to prevent deficiency in most healthy adults — not the amount that is optimal for someone who trains, wants to build muscle, or is dieting. For an 80 kg person the RDA works out to about 64 grams a day, which is genuinely low if you lift weights or run.
What active people actually need
The International Society of Sports Nutrition's position stand on protein concludes that, for building and maintaining muscle, most exercising adults do well on roughly 1.4 to 2.0 grams per kilogram of body weight per day. That is close to double the RDA. Within that band:
- Around 1.6 g/kg is a sensible default for people who train regularly and want to support muscle.
- Higher intakes, toward 2.0 g/kg or a little above, are useful when you are in a calorie deficit, because extra protein helps preserve muscle and keeps you full while you lose fat.
You can get your own target instantly with the protein calculator, which applies these factors based on your weight and goal.
Does timing and per-meal amount matter?
Total daily protein is by far the most important factor. That said, spreading your intake across the day — roughly three to four meals each containing a meaningful serving of protein — is a practical way to hit a higher daily total and may modestly support muscle protein synthesis compared with cramming it all into one meal. You do not need to obsess over a post-workout "anabolic window"; getting your daily total is what counts.
Can you eat too much protein?
For healthy adults with normal kidney function, higher-protein diets within the ranges above are well tolerated, and research has not shown harm to the kidneys from them. The practical ceiling is usually your overall diet: calories still count, and protein displaces carbs and fat, so more is not automatically better. If you have existing kidney disease, protein intake is something to manage with your doctor rather than a calculator.
Putting it together
For most active adults, aiming for about 1.6 g/kg per day — nudging higher when dieting — is a well-supported, achievable target. Use the protein calculator to get your number, then check how it fits your overall calories with the macro calculator.
These are general estimates for healthy adults, not medical advice. If you have kidney disease or another medical condition, are pregnant, or have a history of disordered eating, talk to a doctor or registered dietitian before changing your protein intake. See our methodology for the sources behind these ranges.