Protein Calculator
Calculate your daily protein requirement based on body weight, activity level and fitness goal — from RDA minimums to muscle-building targets.
How to use the Protein Calculator
- Enter your inputs into the Protein Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The protein targets
RDA: 0.36 g/lb (0.8 g/kg) · · · Active: 0.7–1.0 g/lb (1.6–2.2 g/kg) · · · Cutting + training: 1.0–1.4 g/lb (2.3–3.1 g/kg)
The RDA prevents deficiency; modern research supports higher intakes for active adults and those losing weight. Older adults benefit from higher protein due to anabolic resistance.
Worked example
A 180 lb adult who lifts weights and is cutting: 180 × 1.0 g/lb = 180 g protein/day. Distributed across 4 meals: 45 g per meal. Realistic structure: 30 g breakfast eggs + cottage cheese; 50 g lunch chicken; 50 g dinner salmon; 30 g whey shake.
Frequently asked questions
Can you eat too much protein?
For healthy adults, intakes up to 1.6 g/lb (3.5 g/kg) have not shown harm in research. People with kidney disease should consult a physician. Excess protein converts to glucose or fat, just like any excess calorie.
What's the best protein source?
Quality matters less than total quantity for most adults eating mixed diets. Animal sources tend to be more complete and digestible; plant sources can be combined to provide all essential amino acids. Whey is the gold standard for athletes.
How does protein help with weight loss?
High protein preserves muscle during caloric deficit and is the most satiating macronutrient. Two big effects: more fat (less muscle) loss and less hunger.