Protein intake is often measure in percentage of daily calories, with 12-20% of calories from protein being a good range (I know others will disagree with me, but I think the ADA has healthier recommendations that many "diet" plans). YOu would have to then determine how many calories a day you need, take 12-20%--or whatever your protein goal is--of that to get the number of calories of protein you will aim for, then divide that number by 4 (there are 4 calories in each gram of protein, 4 in each gram of carbs, 9 in each gram of fat, and 7 in each gram of alcohol) to come up with the number of grams of protein per day you are aiming for.