How to use the protein calculator
- Choose kilograms or pounds.
- Enter your body weight.
- Pick the situation that describes you best: everyday health, age 65 or older, regular exercise, or strength training to build muscle.
- Choose how many meals you eat a day to see grams per meal.
How protein needs are calculated
Protein targets are set per kilogram of body weight. The calculator multiplies your weight by the range for your situation:
| Situation | g per kg a day | Source |
|---|---|---|
| Minimum for healthy adults | 0.8 | Recommended Dietary Allowance (RDA), National Academies |
| General target | 1.2–1.6 | Dietary Guidelines for Americans, 2025–2030 |
| Adults 65 and older | at least 1.0–1.2 | PROT-AGE Study Group, 2013 |
| Regular exercise or sport | 1.4–2.0 | International Society of Sports Nutrition position stand, 2017 |
| Strength training to build muscle | 1.6–2.2 | Morton et al., British Journal of Sports Medicine, 2018 |
The RDA of 0.8 g/kg is the amount that meets the needs of nearly all healthy adults. It's a floor, not a goal. The 2025–2030 Dietary Guidelines, released in January 2026, set a higher everyday goal of 1.2 to 1.6 g/kg and advise eating protein at every meal. The PROT-AGE group recommends that people over 65 get at least 1.0 to 1.2 g/kg, and 1.2 or more if they're active. The ISSN puts most exercising people at 1.4 to 2.0 g/kg. A 2018 analysis of 49 trials by Morton and colleagues found that muscle gains from strength training leveled off at about 1.6 g/kg, with some people benefiting up to 2.2.
Worked example
These are the calculator's defaults: a body weight of 70 kg, the general target, and 3 meals a day.
- Lower end: 70 × 1.2 = 84 g
- Upper end: 70 × 1.6 = 112 g
- Daily target: 84 – 112 g, or about 28 to 37 g per meal
- Calories from protein: 84 × 4 = 336 to 112 × 4 = 448 kcal
- RDA minimum for comparison: 70 × 0.8 = 56 g
In pounds, the default of 154 lb is 69.85 kg, which gives the same 84 – 112 g after rounding.
Protein in common foods
| Food | Typical portion | Protein |
|---|---|---|
| Chicken breast, cooked | 100 g (3.5 oz) | about 31 g |
| Eggs | 2 large | about 12 g |
| Greek yogurt, plain | 170 g (6 oz) | about 17 g |
| Lentils, cooked | 1 cup | about 18 g |
| Salmon, cooked | 100 g (3.5 oz) | about 25 g |
Spreading protein through the day works better than eating most of it at dinner. About 20 to 40 g per meal is a practical target for most adults. Both animal and plant foods count. People who eat no animal foods may want to aim toward the upper end, since some plant proteins are digested less completely.
When to be careful
If you have chronic kidney disease, don't raise your protein without advice. Doctors often limit protein to protect the kidneys, and the PROT-AGE group makes the same exception. If you carry a lot of body fat, base your target on a healthy weight for your height rather than your current weight, or you'll overestimate. Pregnancy and breastfeeding raise needs too. A doctor or registered dietitian can give you a personal target. To see protein next to carbs and fat, try the macro calculator.
Frequently asked questions
How much protein do I need a day?
At least 0.8 g per kg of body weight, which is 56 g for a 70 kg (154 lb) adult. The 2025–2030 Dietary Guidelines aim higher, at 1.2 to 1.6 g/kg (84 to 112 g at 70 kg). People who exercise hard or are over 65 often benefit from the upper part of that range or more.
Can you eat too much protein?
For healthy adults, intakes up to about 2 g/kg a day appear safe in studies. Very high intakes leave less room for fiber-rich carbohydrates and healthy fats. People with kidney disease should follow their doctor's limits.
Do I need protein shakes?
No. Most people can reach their target with ordinary foods such as meat, fish, eggs, dairy, beans and soy. Shakes are just a convenient option if you struggle to fit enough protein into meals.
Should I use my current weight or my goal weight?
Use your current weight if you're in or near the healthy range. If you have a lot of weight to lose, use a healthy weight for your height. That gives a realistic target, because extra body fat doesn't raise protein needs much.
Related calculators
- Macro Calculator — Split your daily calories into grams of protein, carbs and fat, with preset or custom percentages and grams per meal.
- Calorie Calculator — Daily calories to maintain your weight, plus gradual targets for losing or gaining, using the Mifflin-St Jeor equation.
- Lean Body Mass Calculator — Lean body mass from your height and weight with the Boer, James and Hume formulas, plus the body fat each implies.
- Carbohydrate Calculator — How many grams of carbohydrate a day fit 45–65% of your calories, with low, middle and high levels and grams per meal.
Results are estimates for general information and are not medical advice. Talk to a doctor or other qualified professional about your health. See our disclaimer.