Your daily protein need depends on your body weight, activity level, and goals. The baseline recommendation for healthy adults is 0.8 grams of protein per kilogram of body weight (about 0.36 grams per pound). For a 150-pound person, that works out to roughly 54 grams a day. But that number is a minimum to prevent deficiency, not an optimal target, and most active people need significantly more.
Below you’ll find the specific multipliers for every common goal and life stage, so you can run your own calculation in seconds.
The Basic Formula
Every protein calculation starts the same way:
Your weight in pounds ÷ 2.2 = your weight in kilograms
Then multiply that number by the gram-per-kilogram figure that matches your situation. For example, a 180-pound person weighs about 82 kilograms. At the baseline of 0.8 g/kg, that’s 66 grams of protein per day. At a more active multiplier of 1.4 g/kg, it jumps to 115 grams.
Protein Ranges by Activity Level
The right multiplier depends on how much and how intensely you move throughout the week:
- Sedentary (little or no exercise): 0.8 g/kg per day
- Light exercise or recreational activity: 0.8–1.0 g/kg per day
- Regular moderate exercise or moderate endurance training: 1.2–1.5 g/kg per day
- Ultra-endurance training (marathon, triathlon): 1.2–2.0 g/kg per day
- Strength training or bodybuilding: 1.6–2.0 g/kg per day
The International Society of Sports Nutrition puts the general range for most exercising people at 1.4 to 2.0 g/kg per day. If you work out three to five times a week with a mix of cardio and weights, landing somewhere around 1.4–1.6 g/kg is a solid starting point.
Protein for Muscle Growth
If your primary goal is building muscle, the research points to a clear threshold: you need more than 1.3 g/kg per day to reliably gain muscle mass, and dropping below 1.0 g/kg is associated with muscle loss over time. The practical sweet spot for most people lifting weights consistently is 1.6 to 2.0 g/kg per day.
For a 170-pound lifter (77 kg), that translates to roughly 123 to 154 grams of protein daily. Going above 2.0 g/kg is unlikely to hurt, but the additional muscle-building benefit tapers off. Your body can only use so much protein for repair at one time.
Protein During Weight Loss
When you’re eating fewer calories than you burn, protein becomes even more important. It protects muscle tissue that your body might otherwise break down for energy. Research consistently shows that 1.2 to 1.6 g/kg per day preserves lean mass and improves body composition during a calorie deficit in both younger and older adults.
If you’re also training hard while cutting calories, the target goes higher. Recommendations for athletes in a deficit range from 1.6 to 2.4 g/kg per day, with some evidence supporting up to 2.7 g/kg for resistance-trained individuals. Beyond about 2.4 g/kg, though, additional protein doesn’t appear to spare any more muscle. A reasonable target for most people dieting and exercising is 1.6 to 2.0 g/kg.
Protein Needs Over Age 65
Aging muscles become less efficient at using dietary protein to maintain themselves, a problem that contributes to sarcopenia, the gradual loss of muscle mass that leads to frailty and loss of independence. The Administration for Community Living and several research groups recommend older adults aim for 1.0 to 1.2 g/kg per day, roughly 25 to 50 percent more than the standard 0.8 g/kg baseline.
For a 160-pound older adult (73 kg), that means targeting 73 to 88 grams daily rather than the 58 grams the standard RDA would suggest.
Protein During Pregnancy and Breastfeeding
The Mayo Clinic recommends 71 grams of protein per day during pregnancy. That number stays roughly the same during breastfeeding. For many women, this represents a noticeable increase over their pre-pregnancy intake, especially those who were previously sedentary and eating closer to the 0.8 g/kg minimum.
How to Spread Protein Across Meals
Total daily intake matters most, but how you distribute it throughout the day also makes a difference. Your muscles can only ramp up their repair process so much from a single serving. Research shows that about 30 grams of protein in one meal is enough to maximally stimulate that repair process, and eating 30 to 45 grams per meal across multiple meals produces the strongest association with leg muscle mass and strength.
In practical terms, this means three to four meals each containing at least 30 grams of protein will serve you better than eating most of your protein in one large dinner. A chicken breast, a cup of Greek yogurt, or a scoop and a half of whey protein each get you close to that 30-gram mark.
Quick Reference Calculation
Here’s how to calculate your number right now. Take a 150-pound person as an example (150 ÷ 2.2 = 68 kg):
- Sedentary, general health: 68 × 0.8 = 54 g/day
- Moderately active: 68 × 1.2 = 82 g/day
- Building muscle: 68 × 1.6 = 109 g/day
- Losing fat while training: 68 × 2.0 = 136 g/day
- Over 65, maintaining muscle: 68 × 1.1 = 75 g/day
Swap in your own weight, pick the multiplier that fits your goal, and you have a daily target accurate enough to guide your meals.
Is Too Much Protein Dangerous?
For people with healthy kidneys, high protein intake does not appear to cause kidney damage. A large nationally representative study found that protein intakes of 1.4 g/kg per day and above were not associated with increased mortality in people with normal kidney function. In fact, very low intake (below 0.6 g/kg) was linked to higher mortality risk.
The picture changes for people with existing kidney disease. Impaired kidneys struggle to filter the waste products of protein metabolism, so anyone with reduced kidney function should work with their care team to set an appropriate limit. For everyone else, intakes in the 1.2 to 2.4 g/kg range are well-supported by current evidence and widely used by nutrition professionals without safety concerns.