How much protein do you need a day?
This free calculator turns your body weight, activity, age, and goal into a daily protein target in grams — then splits it across your meals and shows how much your current eating already covers. Move the slider and everything updates instantly.
Your daily protein target
82 grams of protein a day
Plant-based instead? See the vegan plant protein
Educational estimate only, not medical advice or a diagnosis. Protein needs change with health conditions — talk to a doctor or registered dietitian before making a big change.
Protein is the one macronutrient where the official minimum and the practical target are genuinely different numbers. The Recommended Dietary Allowance is set at the level that prevents deficiency, not the level that supports training, fat loss, or holding on to muscle as you age. That gap is why two credible sources can tell you 55 grams and 130 grams for the same person.
Quick answer: The RDA for protein is 0.8 grams per kilogram of body weight, which is about 55 g a day for a 150 lb adult. Most people doing anything active do better in the 1.2 to 1.6 g per kg range, and 1.6 to 2.2 g per kg is the range used for building muscle. Spread it across the day in 15 to 30 gram portions rather than one large meal.
Key Takeaways
- 0.8 g per kg is the floor that prevents deficiency, not the target for an active person.
- 1.2 to 1.6 g per kg is where most adults benefit, including for healthy aging.
- Building muscle sits at 1.6 to 2.2 g per kg, alongside actual resistance training.
- Adults over 65 need more, not less, because muscle responds less readily to protein.
- 15 to 30 g per meal is the practical target; very large single servings add little.
- Food comes first. A powder is for closing a gap you cannot close with meals.
How the calculator works
It starts from grams of protein per kilogram of body weight, the standard way protein is prescribed. The Recommended Dietary Allowance is 0.8 g per kg, or 0.36 g per pound, which works out to roughly 55 grams a day for a 150 pound adult.[1]How much protein do you need every day? — Harvard Health Publishing View source The calculator treats that as the floor and then raises it based on your activity, goal, and age.
Higher targets are not a fringe position. Reviews of the evidence and current expert commentary put the useful range for most adults at 1.2 to 1.6 g per kg, particularly for metabolic health and for preserving muscle with age.[2]How much protein should we really be eating? Five things to know — Stanford Medicine (2026) View source For people actively building muscle, the range moves up to 1.6 to 2.2 g per kg.
One adjustment matters and most calculators skip it: if you carry a lot of excess weight, multiplying your total weight by a protein factor overshoots, because fat mass does not need feeding. That is why the tool asks about your build and works from a leaner reference weight instead.
| Who you are | Grams per kg | Grams per lb | A 150 lb (68 kg) adult |
|---|---|---|---|
| RDA floor, sedentary | 0.8 | 0.36 | About 55 g |
| General health, lightly active | 1.0–1.2 | 0.45–0.55 | About 68–82 g |
| Active, or losing fat | 1.2–1.6 | 0.55–0.73 | About 82–109 g |
| Building muscle | 1.6–2.2 | 0.73–1.0 | About 109–150 g |
| Adults 65+ | 1.2–1.6 | 0.55–0.73 | About 82–109 g |
Long-term intake around 2 g per kg per day is considered safe for healthy adults, with the tolerable upper limit placed considerably higher for well-adapted people.[3]Wu G. Dietary protein intake and human health (2016) — PubMed 26797090 View source None of that applies if you have kidney or liver disease, where protein is prescribed individually.
Why per-meal distribution matters
Your daily total is only half the picture. General guidance is 15 to 30 grams of protein at each meal, and intakes above roughly 40 grams in one sitting do not appear to add much for muscle building.[4]Are you getting too much protein? — Mayo Clinic Health System View source Most people are badly skewed: a carb-heavy breakfast, a light lunch, and then a large dinner that carries the whole day.
That is usually where a shake earns its place. Not as a replacement for food, but as the thing that turns a 5 gram breakfast into a 30 gram one without cooking.
Chocolate Whey Protein — 12 oz
Grass-fed, ultra-filtered whey concentrate, unsweetened, non-GMO and rBGH free. One level scoop in 8 oz of water, milk, or juice. The straightforward pick if dairy agrees with you.
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Vegan Plant Protein — 22 g per scoop
Pea protein isolate with sprouted quinoa, amaranth, and algae protein, plus 4500 mg BCAAs and 3350 mg L-glutamine. A 30 g scoop delivers 22 g of protein, 30 servings per tub. Dairy free and gluten free. Also in vanilla.
Shop Plant Protein →Frequently Asked Questions
How much protein do I need per day? +
The RDA is 0.8 g per kilogram of body weight, roughly 55 g a day for a 150 lb adult. That is a deficiency-prevention floor. Most active adults do better between 1.2 and 1.6 g per kg, which is about 82 to 109 g a day at that same body weight.
How much protein per day to build muscle? +
Between 1.6 and 2.2 g per kilogram of body weight, paired with resistance training. For a 180 lb (82 kg) person that is roughly 130 to 180 g a day. Going above that range has not been shown to add further muscle, and the training stimulus matters more than the extra grams.
How much protein per day to lose weight? +
Aim for 1.2 to 1.6 g per kg while in a calorie deficit. Higher protein helps you hold on to muscle while losing fat and keeps you fuller, so more of the weight you lose comes from fat. For a 160 lb woman that is roughly 87 to 116 g a day.
Is 100 g of protein a day a lot? +
It depends entirely on your size. For a 130 lb sedentary adult, 100 g is well above what is needed. For a 190 lb person building muscle it is on the low side. As a rule of thumb, 100 g suits an active adult somewhere around 140 to 180 lb.
Is 30 g of protein in one meal too much? +
No, 30 g is close to ideal. General guidance is 15 to 30 g per meal, and that amount is enough to trigger the muscle-building response in most adults. What adds little is going far beyond it, since single servings above about 40 g do not appear to give a proportional benefit.
How much protein per kg for muscle gain? +
1.6 to 2.2 g per kg is the working range. The lower end is enough for most people training a few times a week; the upper end is for lean, hard-training individuals or anyone in a calorie deficit who still wants to add muscle. Consistency beats chasing the top of the range.
How much protein per day for a 70 kg man? +
The RDA works out to 56 g. For general health and light activity, 70 to 84 g. If he trains regularly or is losing fat, 84 to 112 g. If he is actively building muscle, 112 to 154 g a day. Which number applies depends on training, not on age or gender alone.
Can you eat too much protein? +
For healthy adults, long-term intakes around 2 g per kg a day are considered safe, and the practical problem with going higher is usually crowding out other foods rather than harm. The picture is completely different in kidney or liver disease, where protein must be set by your clinician.
What are the signs you need more protein? +
Common signals are constant hunger between meals, losing strength despite training, slow recovery from workouts or illness, hair thinning, and nails that break easily. None of these prove a shortfall on their own, but together with a low intake they point strongly at it.
Are 2 eggs a day enough protein? +
No. Two large eggs supply roughly 12 to 13 g of protein, which is a reasonable start to a meal but well under a 15 to 30 g target for that meal and a small fraction of a daily total. Eggs work best combined with another source such as Greek yogurt, beans, or a shake.
How much protein should I eat at each meal? +
Aim for 15 to 30 g in every meal rather than loading it all into dinner. Spreading it out gives your body a repeated signal to build and repair muscle across the day. Breakfast is where most people fall short, and it is the easiest meal to fix.
Do older adults need more protein? +
Yes. Muscle becomes less responsive to protein with age, so adults over 65 generally need 1.2 to 1.6 g per kg rather than the 0.8 g per kg RDA. Pairing that intake with resistance training is what actually protects muscle mass and strength over time.
Whey or plant protein, which should I choose? +
If dairy agrees with you, whey is the simpler and cheaper option and digests quickly. Choose plant protein if you are vegan, lactose sensitive, or react badly to dairy. A good pea-based blend with added amino acids closes most of the historical gap between the two.
Do I actually need a protein powder? +
Only if you cannot reach your target from food. Powder is a convenience, not a requirement, and whole foods bring fibre, vitamins, and minerals along with the protein. If your calculator result shows little or no gap, you do not need one.
Looking for a different number? See all free supplement calculators.
Medical Disclaimer
This calculator provides general educational estimates for healthy adults only. It is not medical advice, a diagnosis, or a nutrition prescription, and it cannot account for your medical history, medications, or lab results.
Talk to a doctor or a registered dietitian before changing your protein intake, and in particular if you:
- have kidney disease or reduced kidney function, where protein is often deliberately restricted;
- have liver disease, diabetes, or any chronic condition;
- are pregnant or breastfeeding, since needs are higher and should be set for you;
- are on dialysis or following a medically prescribed diet;
- are setting an intake for anyone under 18 years of age.
Protein powders are food supplements, not meal replacements or treatments. If you have a dairy allergy, avoid whey products entirely, and check every label if you have a food allergy.
These statements have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.