Quick answer
How much protein do I need a day?
The minimum for healthy adults is 0.8 g per kg of body weight (about 0.36 g per lb), but that is a floor to avoid deficiency, not an optimum. If you strength train or are losing weight, aim for 1.6 to 2.2 g per kg (0.7 to 1 g per lb): a large meta-analysis found muscle gains level off around 1.6 g/kg. For a 70 kg (154 lb) person that is about 56 g at the minimum and 112 to 154 g when training.
On this page
How to use the protein calculator
- Enter your body weight in kg or lb. If you have a lot of weight to lose, use your goal weight instead, so the target is not inflated.
- Pick your goal: maintain, build muscle or lose fat.
- Pick your activity level and tick 65 or older if it applies; older adults need more protein to hold on to muscle.
- Read your daily target (the middle of your range), the full range, grams per pound, and how much to eat at each of four meals.
Protein targets by goal
The calculator multiplies your body weight by a range of grams per kilogram. The range depends on your goal and how active you are.
| Situation | g per kg | g per lb |
|---|---|---|
| Sedentary adult (minimum, RDA) | 0.8–1.0 | 0.36–0.45 |
| Adult 65+ | 1.0–1.2 | 0.45–0.55 |
| Active, maintaining | 1.2–1.6 | 0.55–0.73 |
| Building muscle | 1.6–2.2 | 0.73–1.0 |
| Losing fat while training | 1.6–2.2 | 0.73–1.0 |
| Lean athlete in a deficit | 1.8–2.4 | 0.82–1.1 |
Protein per day by body weight
Quick reference for the two most common targets. Use the minimum if you don’t exercise, and the training range if you do.
| Body weight | Minimum (0.8 g/kg) | Training (1.6–2.2 g/kg) |
|---|---|---|
| 50 kg (110 lb) | 40 g | 80–110 g |
| 60 kg (132 lb) | 48 g | 96–132 g |
| 70 kg (154 lb) | 56 g | 112–154 g |
| 80 kg (176 lb) | 64 g | 128–176 g |
| 90 kg (198 lb) | 72 g | 144–198 g |
| 100 kg (220 lb) | 80 g | 160–220 g |
If you carry a lot of body fat, these numbers overestimate what you need. Calculate from your goal weight instead.
Why protein matters
Protein supplies the amino acids your body uses to build and repair muscle, skin, organs, enzymes and immune cells. Unlike fat and carbohydrate, the body has no dedicated protein store, so it needs a steady supply from food.
- Muscle. Combined with strength training, enough protein builds muscle and protects it during a diet.
- Fullness. Protein is the most filling macronutrient, which helps control appetite in a calorie deficit.
- Higher thermic effect. Your body uses about 20 to 30% of protein’s calories digesting it, compared with under 10% for carbs and fat.
- Healthy ageing. Adequate protein slows the muscle loss that starts in middle age and speeds up after 65.
High-protein foods
| Food | Serving | Protein |
|---|---|---|
| Chicken breast, cooked | 100 g (3.5 oz) | 31 g |
| Lean beef, cooked | 100 g | 26 g |
| Tuna, canned in water | 100 g drained | 25 g |
| Salmon, cooked | 100 g | 22 g |
| Greek yogurt, plain nonfat | 170 g pot | 17 g |
| Cottage cheese | ½ cup (113 g) | 12 g |
| Eggs | 2 large | 12 g |
| Tempeh | 100 g | 20 g |
| Tofu, firm | 100 g | 15–17 g |
| Lentils, cooked | 1 cup | 18 g |
| Chickpeas, cooked | 1 cup | 15 g |
| Whey protein powder | 1 scoop (30 g) | 20–25 g |
Animal foods, soy and whey are complete proteins, with all nine essential amino acids. Plant eaters can reach the same target by mixing legumes, soy, grains, nuts and seeds through the day.
How to split protein across the day
Total daily protein matters most. After that, research suggests about 0.4 g per kg per meal, spread over at least four meals, is a good way to keep muscle building ticking over. For a 70 kg person that is roughly 28 to 30 g per meal: a chicken breast, a pot of Greek yogurt with some nuts, or a tofu stir-fry.
The easiest wins are at breakfast, where most people eat the least protein. Eggs, Greek yogurt, cottage cheese or a protein smoothie can add 20 to 30 g without much effort. Once your protein is set, the macro calculator fills in carbs and fat around it.
Can you eat too much protein?
For healthy adults, high-protein diets are well tolerated and have not been shown to harm kidney function. The practical limit is usually appetite and balance: eating so much protein that it crowds out the fibre-rich carbs and healthy fats your body also needs. If you have kidney disease, check with your doctor before raising your intake.
Frequently asked questions
How much protein do I need to build muscle?
Between 1.6 and 2.2 g per kilogram of body weight, which is roughly 0.7 to 1 g per pound. Meta-analyses find gains level off above about 1.6 g/kg, and intakes beyond 2.2 g/kg have not produced extra muscle in controlled trials. Eating more is not harmful for healthy people; it simply stops helping.
How much protein should I eat while losing weight?
More than at maintenance, not less. A deficit is when muscle is most at risk, and protein is the main thing protecting it. Aim for about 1.6 to 2.2 g/kg if you train, and toward the top of that if you are already lean. Protein is also the most filling macronutrient, which makes the deficit easier to hold.
Is too much protein bad for your kidneys?
For people with healthy kidneys, higher protein intakes (up to about 2.2 g/kg and beyond) have not been shown to damage kidney function. If you have chronic kidney disease or reduced kidney function, protein often needs to be limited, so follow your doctor’s advice.
Can my body only absorb 20 to 30 g of protein at a time?
No. That figure comes from studies of how much protein maximally stimulates muscle building in one sitting, and it was misread as an absorption limit. Your gut absorbs essentially all of it. A 2023 study found a 100 g dose still building muscle protein many hours later. Spreading protein across meals is good practice, not a biological requirement.
When is the best time to eat protein?
Total daily intake matters most. Beyond that, splitting it across three to five meals of roughly 0.4 g/kg each, including one within a few hours of training, is a sensible way to support muscle protein synthesis through the day.
Do older adults need more protein?
Yes. Muscle responds less to protein with age, so expert groups recommend 1.0 to 1.2 g/kg a day for healthy adults over 65, and more for those who are ill or very active. Tick 65 or older in the calculator to apply this.
Can I get enough protein on a vegetarian or vegan diet?
Yes. Combine legumes, soy foods (tofu, tempeh, edamame), seitan, whole grains, nuts and seeds across the day. Aiming for the upper end of your range covers the slightly lower digestibility of some plant proteins.
Do I need protein powder?
No. Powder is convenience, not necessity, and there is no evidence it beats food at the same protein dose. It is useful when you struggle to hit your target from meals, travel often, or want something quick after training.
Sources
- Morton RW, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength. Br J Sports Med, 2018.
- Jäger R, et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr, 2017.
- Schoenfeld BJ, Aragon AA. How much protein can the body use in a single meal for muscle-building? J Int Soc Sports Nutr, 2018.
- Leidy HJ, et al. The role of protein in weight loss and maintenance. Am J Clin Nutr, 2015.
- Bauer J, et al. Evidence-based recommendations for optimal dietary protein intake in older people (PROT-AGE). J Am Med Dir Assoc, 2013.
- Trommelen J, et al. The anabolic response to protein ingestion during recovery from exercise has no upper limit in magnitude and duration in vivo in humans. Cell Rep Med, 2023.
- MedlinePlus (U.S. National Library of Medicine). Dietary proteins.
This calculator gives estimates for healthy adults and is for information only. It is not a diagnosis or a substitute for advice from a doctor or registered dietitian.