The average non athletic person can determine how much protein you need each day by multiplying your body weight by 0.4 (representing 0.4 grams of protein). Thus, an average 150-pound man needs approximately 60 grams of protein daily, which represents about 240 calories. This amount of protein is easily obtained in most diets that include even small servings of meat, fish, eggs, milk products, and beans.
If you are a strength athlete you need about 0.8 grams of protein per pound of bodyweight. Endurance athletes, doing more cardiovascular exercise than strength training, need 0.6 grams of protein per pound of bodyweight.