To calculate your protein intake, multiply your body weight in kilograms by a factor that matches your activity level and goals. The simplest starting point: take your weight in pounds, divide by 2.2 to get kilograms, then multiply by a number between 0.8 and 2.4 depending on your situation. For most adults, the sweet spot falls between 1.2 and 1.6 grams per kilogram per day.
The Basic Formula
Every protein calculation starts the same way:
- Step 1: Convert your weight to kilograms. Divide your weight in pounds by 2.2. A 170-pound person weighs about 77 kg.
- Step 2: Multiply your weight in kilograms by your protein factor (see below).
For decades, the Recommended Dietary Allowance sat at 0.8 grams per kilogram, or about 0.36 grams per pound. That number was designed as a minimum to prevent deficiency, not an optimal target. The 2025–2030 Dietary Guidelines for Americans raised the recommendation to 1.2 to 1.6 grams per kilogram per day for adults, which is 50 to 100 percent more than the old minimum. For that same 170-pound person, the updated range works out to roughly 92 to 123 grams of protein per day.
Which Multiplier to Use
Your ideal protein factor depends on what your body is doing right now. Here’s how to pick yours:
- General health, light activity (1.2–1.6 g/kg): This is the new standard range for most adults. If you exercise a few times a week and aren’t trying to dramatically change your body composition, aim here.
- Building muscle or training hard (1.6–2.2 g/kg): Strength training increases your body’s demand for protein. The higher end of this range suits people doing intense resistance training multiple days per week.
- Losing weight while preserving muscle (1.6–2.4 g/kg): When you cut calories, your body will break down muscle for energy unless you provide enough protein to protect it. Research on athletes in a caloric deficit recommends 1.6 to 2.4 grams per kilogram. Going above 2.4 g/kg doesn’t appear to offer additional muscle-sparing benefits.
- Adults over 65 (1.0–1.2 g/kg minimum): Aging bodies become less efficient at using dietary protein to maintain muscle. Recommendations for older adults start at 1.0 to 1.2 grams per kilogram to help prevent age-related muscle loss.
- Pregnancy and breastfeeding (1.1 g/kg): The RDA during pregnancy and lactation is 1.1 grams per kilogram, which works out to roughly 71 grams per day for an average-weight woman, up from 46 grams at baseline.
A Quick Example
Say you weigh 180 pounds and you’re strength training three days a week while eating in a slight caloric deficit to lose fat. Here’s your math:
180 ÷ 2.2 = 81.8 kg
Using the weight-loss-with-training range of 1.6 to 2.4 g/kg:
81.8 × 1.6 = 131 grams per day (lower end)
81.8 × 2.4 = 196 grams per day (upper end)
A reasonable target for this person would be somewhere around 150 to 170 grams daily, adjusting based on how training recovery feels and whether body composition is moving in the right direction.
What to Do If You’re Significantly Overweight
If you carry a lot of extra body fat, using your total body weight in the formula can overestimate your protein needs, since fat tissue doesn’t require the same protein support that muscle does. Research on obese older adults found that 1.2 grams per kilogram of total body weight was the threshold needed to gain muscle during a weight loss program. That’s a practical number to use even at a higher body weight.
Another approach is to calculate based on your goal weight or your lean body mass (everything that isn’t fat). If you know your body fat percentage, you can estimate lean mass: multiply your weight by (1 minus your body fat percentage as a decimal). A 250-pound person at 35% body fat has roughly 163 pounds of lean mass, or about 74 kg. Multiplying 74 kg by 1.6 to 2.0 gives a range of 118 to 148 grams per day, which is more realistic than plugging 250 pounds into the formula at higher multipliers.
How to Spread Protein Across the Day
Your body can only use so much protein at once for muscle building. Studies show that the muscle-building response maxes out at roughly 30 to 45 grams of protein per meal. Eating 80 grams in one sitting won’t stimulate twice as much muscle repair as eating 40 grams. The excess gets used for energy or other functions, but it won’t give you an extra muscle-building advantage.
For most people, this means spreading your daily target across three to four meals works better than loading it all into one or two. If your target is 150 grams, aiming for roughly 35 to 40 grams at each of four meals is more effective than eating 20 grams at breakfast, 20 at lunch, and 110 at dinner. This even distribution matters more as you get older. Research suggests that older adults who consistently hit 30 to 40 grams per meal retain more leg muscle mass and strength than those who eat the same total protein but cluster it unevenly.
Tracking Your Intake
Once you have your daily target, you need a rough sense of how much protein is in common foods. Some reference points: a chicken breast has about 30 grams, a large egg has 6, a cup of Greek yogurt has 15 to 20, a can of tuna has about 25, a cup of cooked lentils has around 18, and a scoop of most protein powders delivers 20 to 25 grams.
You don’t necessarily need to weigh and log every meal forever. Spending one to two weeks tracking with a food app gives you a reliable mental map of where your protein actually comes from. Most people discover they eat far less protein at breakfast and lunch than they assumed, and that small additions (an extra egg, a handful of nuts, a side of cottage cheese) close the gap faster than a complete diet overhaul.
If your daily target feels impossibly high at first, ramp up gradually over a week or two. A sudden jump in protein intake can cause digestive discomfort. Adding 10 to 15 grams per day until you reach your goal gives your system time to adjust.