Protein is the nutrient people most often under-eat when they train or diet, and the one with the clearest evidence for a target above the bare minimum. This calculator gives a daily range in grams for your weight and goal, then splits it across meals and translates it into real food.
How it is calculated
Targets are set in grams per kilogram of body weight, which is how the research reports them:
- Minimum for healthy adults (RDA): 0.8 g/kg. Enough to avoid deficiency, not optimal for training.
- General fitness: 1.2–1.6 g/kg.
- Building muscle: 1.6–2.2 g/kg. Meta-analyses find gains plateau around 1.6 g/kg for most people; going higher costs nothing but has a small extra effect.
- Losing fat while keeping muscle: 1.8–2.4 g/kg. Higher protein in a deficit preserves lean mass and reduces hunger.
- Age 65 and over: 1.0–1.2 g/kg to counter age-related muscle loss.
- Pregnancy: about 1.1–1.3 g/kg in the second and third trimesters.
- Breastfeeding: 1.3–1.9 g/kg. The official RDA is 1.3 g/kg; a 2020 study of exclusively breastfeeding women measured needs of about 1.7–1.9 g/kg, so the range runs up to 1.9.
In pounds, multiply by 0.45: 1.6–2.2 g/kg is 0.73–1.0 g per pound, so the popular “1 gram per pound” rule sits at the top of the muscle-building range.
The calculator shows the middle of the range as the main number and the full range under it. For lean people the numbers are accurate as-is. For people carrying a lot of extra weight, using goal weight instead of current weight avoids overshooting: enter it in the optional Goal weight field. The table at the end of the results lists every weight from 100 to 300 lb (45 to 136 kg).
Example
A 75 kg (165 lb) person training three times a week to build muscle: 75 × 1.6–2.2 = 120–165 g a day, about 140 g in the middle. Over four meals that is about 35 g each, roughly a chicken breast, a large serving of Greek yogurt or a scoop of whey with milk. To check what you actually eat, add up your meals in the protein in food calculator.
Does timing matter?
Less than total intake, but somewhat. Spreading protein into 3–5 servings of 25–40 g gives more muscle protein synthesis than the same total in one or two meals, and a serving within a few hours of training helps. The "anabolic window" of 30 minutes is a myth; the day matters, not the minute.
Frequently asked questions
How much protein do I need to build muscle?
About 1.6–2.2 g per kilogram of body weight per day. Research shows most of the benefit by 1.6 g/kg; higher intakes add a little more and help if you are also in a deficit.
Is too much protein bad for your kidneys?
Not for healthy kidneys. Studies of up to a year in healthy, resistance-trained adults eating up to about 3.3 g/kg found no harm to kidney or liver markers. People with existing kidney disease should follow their doctor’s limits.
Should I calculate protein from lean mass or total weight?
Total weight works for most people. If your BMI is over 30, use your goal weight or lean mass, otherwise the target overshoots what your muscle mass can use.
How much protein per meal can the body absorb?
The body absorbs almost all of it; the old "30 g limit" refers to how much muscle protein synthesis is stimulated per serving. Servings of 25–40 g are a practical sweet spot, and larger meals are not wasted, just used more slowly.
Is 200g of protein a day too much?
For most people it is more than they need, but not harmful if the kidneys are healthy. 200 g is the top of the muscle-building range (2.2 g/kg) for someone who weighs about 91 kg (200 lb). A lighter person gets no extra muscle from it, just extra calories. Studies of up to a year in healthy, resistance-trained adults eating up to about 3.3 g/kg found no harm to kidney or liver markers.
Is eating 100g of protein a day enough?
It depends on your weight and goal. 100 g covers the 0.8 g/kg minimum for anyone up to 125 kg (276 lb), and the 1.6 g/kg muscle-building target for someone up to 62.5 kg (138 lb). Heavier people who train need more. Enter your weight above to see your own range.
How much protein does a 150 pound woman need?
At least 54 g a day, the 0.8 g/kg minimum for 150 lb (68 kg). If she exercises 2–4 times a week, 82–109 g. To build muscle, 109–150 g, and while losing fat, 122–163 g. A man of the same weight needs the same: protein follows weight and activity, not sex.
How much protein does a 200 lb male need daily?
At least 73 g a day, the 0.8 g/kg minimum for 200 lb (91 kg). With regular exercise, 109–145 g. To build muscle, 145–200 g, so the popular “1 gram per pound” rule is the top of that range. If much of the 200 lb is body fat, base the target on goal weight instead.
Is 100g of protein a day enough for a woman?
For most women, yes. 100 g covers the 0.8 g/kg minimum at any weight up to 276 lb (125 kg). It also covers the 1.6 g/kg muscle-building target for a woman up to 138 lb (62.5 kg). A heavier woman who lifts weights or is in a calorie deficit needs more; the table above shows the range for each weight.
How much protein do I need by age?
Adults from 19 to 64 have the same minimum, 0.8 g per kg of body weight a day, and need more only for training or weight loss. From age 65, the PROT-AGE expert group recommends at least 1.0–1.2 g/kg to protect muscle, 1.2 g/kg or more for active people and 1.2–1.5 g/kg for people with acute or chronic illness. For 150 lb (68 kg) at 70, that is 68–82 g a day. Children and teens need more per kg while they grow; ask a pediatrician.
How much protein do I need to lose 20 pounds?
The amount you plan to lose does not change the target; your weight does. While losing fat, eat 1.8–2.4 g per kg (0.82–1.09 g per lb). A 180 lb (82 kg) person needs 147–196 g a day. If you have a lot to lose, use goal weight: 160 lb (73 kg) gives 131–174 g.
How much protein a day to lose belly fat?
No amount of protein burns belly fat on its own, and you cannot choose where the body loses fat first. Fat comes off in a calorie deficit. Protein helps during that deficit: 1.8–2.4 g per kg of body weight keeps muscle and blunts hunger. Choose “Lose fat, keep muscle” above to see your range.
How can I calculate the amount of protein in my food?
On packaged food, multiply the grams of protein per serving on the label by the number of servings you eat. For food without a label, look it up in a nutrient database such as USDA FoodData Central. Cooked chicken breast has about 31 g per 100 g (3.5 oz), one egg about 6 g. The food table in the results shows how much of common foods covers your target.
Do I need protein powder?
No. Powder is a convenient, cheap source, not a requirement. If you hit your target from meat, dairy, eggs, legumes and soy, there is no extra benefit from supplements.
How many grams of protein a day to lose weight?
1.8 to 2.4 g per kilogram of body weight — higher than you would eat at maintenance, because protein is what protects muscle while you are in a deficit, and it blunts hunger. For an 80 kg (176 lb) person that is roughly 145 to 190 g a day. Pick “Lose fat, keep muscle” above and the calculator gives your own range.
Read more
- How much protein do you need by age?Protein needs per kilogram are highest in toddlers, settle at 0.8 g/kg in adults and rise again after 65. A table of the official values by age, what they mean at your weight, and why experts ask older adults to eat more than the RDA.
- Is 100 grams of protein a day enough?It depends on two things, and one of them is not up for debate. A table of what 100 g works out to at every body weight, where it runs short, and whether 200 g is too much — with the studies the targets come from.
- How much protein per day to lose weight for a womanWhile losing weight, aim for 1.8 to 2.4 g of protein per kg of body weight, the same rule as for men. A table by weight from 120 to 250 lb, a sample day with 134 g, and when to use your goal weight instead.
- How long it takes to lose 20 pounds on a 500-calorie deficitTwenty weeks, if the arithmetic held — and it does not quite. Here is the table for every deficit from 250 to 1,000 kcal, why the last few pounds take longer than the first, and what 500 calories below maintenance actually means on a plate.
Sources
- Morton RW et al. A systematic review, meta-analysis and meta-regression of protein supplementation on resistance training-induced gains. Br J Sports Med, 2018
- Jäger R et al. International Society of Sports Nutrition position stand: protein and exercise. JISSN, 2017
- Bauer J et al. Evidence-based recommendations for optimal dietary protein intake in older people (PROT-AGE). JAMDA, 2013
- Dietary Reference Intakes for Macronutrients. National Academies, 2005
- Health Canada: Dietary Reference Intakes tables, reference values for macronutrients (protein RDA by age, pregnancy and lactation)
- Protein requirements of healthy lactating women are higher than the current recommendations. Curr Dev Nutr, 2020 (conference abstract)
- USDA FoodData Central: protein content of foods
By Calcelate Team. Formula from the sources above.
- 2026-09-14 · Formula and texts checked