How much protein you need
Protein builds and repairs muscle, bones, skin and enzymes. Needs scale with body weight and rise with physical activity, age and weight loss. This calculator multiplies your weight by a target in grams per kilogram and shows the daily total, the amount per meal and a few food equivalents.
The formula
Protein per day (g) = body weight (kg) × target (g/kg)
Weight in pounds is converted to kilograms by dividing by 2.2. Common targets:
- 0.8 g/kg: the Recommended Dietary Allowance (RDA) for healthy, sedentary adults. It covers basic needs, not optimal performance.
- 1.2 g/kg: active adults and people over 65, who need more protein to keep muscle mass.
- 1.6 g/kg: people training to build muscle. Research finds little extra gain above this level for most.
- 2.0 g/kg: people losing fat while lifting weights, to protect lean mass during a calorie deficit.
Worked example: 180 lb, active
- Weight: 180 ÷ 2.2 = 81.6 kg.
- Protein: 81.6 × 1.2 = 98 g a day.
- Over four meals: about 24 g per meal.
- That is 392 kcal, about 16% of a 2,400 kcal diet.
- As food: about 11 oz of cooked chicken breast, or 16 large eggs, over the day.
Protein by body weight (1.2 g/kg)
| Weight | Per day | Per meal (4 meals) |
|---|---|---|
| 120 lb | 65 g | 16 g |
| 150 lb | 82 g | 20 g |
| 180 lb | 98 g | 24 g |
| 210 lb | 114 g | 29 g |
| 240 lb | 131 g | 33 g |
Spreading protein over the day
Eating 20 to 40 g of protein per meal appears to stimulate muscle repair better than one large serving. Breakfast is often the lightest meal for protein: eggs, Greek yogurt, cottage cheese or a protein shake help balance the day.
Good sources
Per serving, approximately: 3 oz cooked chicken breast 26 g, 3 oz salmon 22 g, 1 cup Greek yogurt 20 g, 1 cup cooked lentils 18 g, 1 large egg 6 g, 1 oz almonds 6 g, 1 cup milk 8 g. Plant proteins work well when you combine sources over the day.
Safety
For healthy adults, intakes up to about 2 g/kg a day are considered safe. People with chronic kidney disease, and some people with liver disease, may need to limit protein: follow your doctor’s advice. If you are overweight, many dietitians base protein targets on your goal weight rather than your current weight. This tool gives general information and does not replace personal medical advice.