Protein Calculator
Pick one of two ways to get a daily protein figure. By goal and activity takes your body weight and what you are doing, and returns a range in grams from the Dietary Guidelines for Americans or the International Society of Sports Nutrition. Daily target takes your age, sex, height, weight, activity level and goal, sets protein at 2.2 grams per kilogram of body weight, and shows calories, carbs and fat beside it. In that mode a 170 lb person gets 170 g whether the goal is to lose, keep or gain weight.
How to use the Protein Calculator
- Pick By goal and activity or Daily target above the form.
- In By goal and activity, choose pounds or kilograms, enter your body weight, pick the line that fits you and press Calculate.
- In Daily target, enter your age, sex, height, weight, activity level and goal, then press Calculate Macros.
- To try other numbers, change any value and press the button again.
How the calculator sets protein
By goal and activity: Protein (g) = weight (kg) × g per kg, for the low and the high end · · · Daily target: Protein (g) = weight (kg) × 2.2 · · · Fat (g) = calories × 25% ÷ 9 · · · Carbs (g) = (calories − protein × 4 − fat × 9) ÷ 4
By goal and activity has three ranges: 1.2 to 1.6 g per kg a day for everyday eating, 1.4 to 2.0 for exercising regularly to gain or keep muscle, and 2.3 to 3.1 for resistance training while cutting calories. A pound is 0.45359237 kg, and the grams are rounded once to whole grams. Daily target uses one rate for everyone, 2.2 g per kg, about 1 g per pound, which is above the 1.4 to 2.0 range. Its calories come from the Mifflin–St Jeor equation times your activity factor, with 500 taken off for weight loss or added for weight gain. Protein and fat are fixed first, at 4 and 9 calories per gram, and carbs fill the calories that are left.
Worked example
By goal and activity: a 170 lb person who exercises regularly and wants to gain muscle weighs 77.1 kg, so 1.4 to 2.0 g per kg gives 108 to 154 g a day. The adult RDA of 0.8 g per kg would be 62 g. Daily target: a 28-year-old man, 5'10" and 170 lb, moderately active, with the goal set to maintain: 2,708 calories, 170 g protein, 338 g carbs and 75 g fat. Switch the goal to lose weight and calories drop to 2,208, carbs to 244 g and fat to 61 g. Protein stays at 170 g.
Frequently asked questions
How much protein is enough for muscle gain?
The 2017 position stand of the International Society of Sports Nutrition says 1.4 to 2.0 g per kg a day is sufficient for most exercising people who are building or keeping muscle. At 170 lb that is 108 to 154 g. It is a general range for most exercising people, and it promises no gain.
Does more protein keep adding muscle?
A 2018 meta-analysis of 49 resistance training studies, with 1,863 participants, found no further gain in fat-free mass from protein supplements once total protein passed about 1.62 g per kg a day. The confidence interval around that figure runs from 1.03 to 2.20, so it is an estimate for groups and not a limit for you.
Why is the range so high when cutting calories?
The same position stand says 2.3 to 3.1 g per kg a day may be needed to keep as much lean mass as possible in resistance-trained people who are eating fewer calories. That line is for trained lifters in a calorie deficit, and the source says may, so it is not a range for everyone. If that is not you, one of the other two lines fits better.
What if I am not training for anything?
The Dietary Guidelines for Americans 2025-2030 give a general goal of 1.2 to 1.6 g per kg a day, adjusted to your calorie needs, with no activity level attached. The Everyday eating line uses that. The National Academy of Medicine recommends at least 0.8 g per kg a day for adults, the RDA. The result shows it too, so you can see both.
Should I be careful if I have kidney disease or am pregnant?
Ask your doctor or a dietitian first, because this page cannot judge either. The National Institute of Diabetes and Digestive and Kidney Diseases says some people with chronic kidney disease may need moderate amounts of protein, and that too little can lead to malnutrition. It advises working with a dietitian or health care professional.
Why doesn't protein change with my goal or activity in Daily target?
That mode uses one rate for everyone, 2.2 g per kilogram of body weight. Activity and goal only move the calorie target, and carbs and fat take up the difference. For separate figures by goal, use By goal and activity.
Can I use a different grams-per-pound rate?
Not on this page, because each line has its own fixed rates. Multiply your weight by the rate you want instead. At 0.8 g per pound, a 170 lb person gets 136 g a day.
Why does Daily target show calories, carbs and fat too?
That mode runs the macro calculator, so one form returns all four numbers. The macro calculator page explains how the calories and the carb and fat split are worked out.