Protein needs scale with body size, so a single number such as 50 grams a day fits almost nobody. This calculator multiplies your weight by a grams-per-kilogram rate drawn from published guidance for your situation, then breaks the total into per-meal targets you can actually plan around.
How to use the protein intake calculator
- Choose pounds or kilograms and enter your body weight.
- Optionally enter a goal weight. If you have significant weight to lose, this keeps the target realistic.
- Pick the description that fits you best, from a mostly inactive adult to someone strength training or losing fat.
- Set meals per day to see how much protein each meal should carry.
- Add your daily calories if you want to see what share of them the protein supplies.
Protein intake formula
To use pounds, divide by 2.2046 first, or multiply pounds by the rate divided by 2.2046 (so 1.6 g/kg is about 0.73 g per pound).
| Situation | Rate (g/kg/day) | Basis |
|---|---|---|
| Healthy adult, mostly inactive | 0.8 | RDA, National Academies |
| Adult 65 or older | 1.0–1.2 | PROT-AGE Study Group, ESPEN |
| Regular exercise or endurance training | 1.2–1.6 | ACSM, AND and Dietitians of Canada joint position (2016) |
| Strength training to build muscle | 1.6–2.2 | ISSN position stand; Morton et al. 2018 meta-analysis |
| Losing fat while keeping muscle | 1.8–2.4 | Sports-nutrition guidance for calorie deficits |
| Pregnancy, second half | 1.1 | RDA |
| Breastfeeding | 1.3 | RDA |
Worked example
A 170-lb person lifting weights four times a week to build muscle, eating four meals a day:
Weight in kilograms: 170 ÷ 2.2046 ≈ 77.1 kg.
Protein: 77.1 × 1.6 = 123 g and 77.1 × 2.2 = 170 g, so 123–170 g per day, with about 147 g as a middle target.
Per meal: 31–42 g across four meals. That protein supplies 494–679 kcal a day.
What these amounts look like on a plate
Typical protein in common foods, based on USDA FoodData Central values (brands and cuts vary):
| Food | Serving | Protein |
|---|---|---|
| Chicken breast, cooked | 3 oz (85 g) | about 26 g |
| Canned tuna, drained | 3 oz | about 20 g |
| Greek yogurt, plain nonfat | 6 oz (170 g) | about 17 g |
| Cottage cheese, 2% | 1 cup | about 24 g |
| Lentils, cooked | 1 cup | about 18 g |
| Black beans, cooked | 1 cup | about 15 g |
| Large egg | 1 | about 6 g |
| Milk | 1 cup | about 8 g |
| Peanut butter | 2 tbsp | about 7 g |
A 35-gram meal might be a chicken breast with a cup of milk, or Greek yogurt with a scoop of cottage cheese and some fruit. Plant-based eaters can reach the same totals with legumes, soy foods and grains; eating a variety across the day covers essential amino acids.
Getting the most from your protein
Spread it out
Research on muscle protein synthesis suggests that three to five protein-containing meals beat one large protein dinner. Breakfast is the meal most people under-serve.
Pair it with training
Extra protein supports muscle only when the muscle is being challenged. Without resistance training, intakes far above about 1.2 g/kg mostly become extra calories. If you are training for strength, the one-rep max calculator helps set loads.
Fit it into your calories
Protein still counts toward your energy budget at 4 kcal per gram. Use the macro calculator to balance protein with carbohydrate and fat at your calorie target, or estimate lean mass with the lean body mass calculator if you prefer protein per kilogram of lean tissue.
Informational only — not medical advice. People with kidney or liver disease, or anyone on a prescribed diet, should follow the protein target set by their clinician.
Frequently asked questions
How much protein do I need a day?
The RDA for healthy adults is 0.8 grams per kilogram of body weight, about 0.36 grams per pound. That is a minimum to avoid deficiency, not an optimum. Active people and older adults are commonly advised to eat 1.0–2.2 g/kg depending on age and training.
Can you absorb more than 30 grams of protein at once?
Your gut absorbs nearly all the protein you eat; the debate is about how much a single meal can push muscle building. Spreading intake over three to five meals of roughly 0.25–0.4 g/kg each is a sensible approach, but total daily protein matters most.
Should I use my current weight or my goal weight?
Use current weight if you are near a healthy weight. If you carry a lot of body fat, protein targets based on total weight run high, so many dietitians use a goal or adjusted weight instead. The optional goal weight field does that.
Is a high-protein diet safe for my kidneys?
For people with healthy kidneys, intakes up to about 2 g/kg have not been shown to cause harm in studies. People with chronic kidney disease are usually told to limit protein, so they should follow their nephrologist's target rather than this calculator.