Calculate your daily protein target based on body weight, activity level, and goal — get gram targets for muscle gain, weight loss, endurance, and senior-specific needs.
🏃 Exercise: 15-30 minutes of elevated heart rate activity.
💪 Intense exercise: 45-120 minutes of elevated heart rate activity.
🔥 Very intense exercise: 2+ hours of elevated heart rate activity.
Proteins are one of three primary macronutrients that provide energy to the human body, along with fats and carbohydrates. Proteins are also responsible for a large portion of the work that is done in cells; they are necessary for proper structure and function of tissues and organs, and also act to regulate them. They are comprised of a number of amino acids that are essential to proper body function, and serve as the building blocks of body tissue.
There are 20 different amino acids in total, and the sequence of amino acids determines a protein's structure and function. While some amino acids can be synthesized in the body, there are 9 essential amino acids that humans can only obtain from dietary sources. Foods that provide all essential amino acids are called complete protein sources.
Protect the body from foreign particles like viruses and bacteria
Help form new molecules and perform chemical reactions
Transmit signals throughout the body to maintain processes
Act as building blocks for cells and body movement
Move molecules throughout the body
This protein calculator is built for adults who want a protein gram target tailored to their body weight, training load, and specific goal. Enter your weight (in pounds or kilograms), activity level, and goal — weight loss, muscle maintenance, muscle gain, or endurance training — and the calculator returns a daily protein target expressed in grams per day and grams per kilogram of body weight. The ranges it uses align with the USDA Dietary Reference Intakes and published sports nutrition research. This tool focuses exclusively on protein, unlike a full macro calculator that distributes all three macronutrients. If your training, age, health status, or dietary pattern (such as plant-based eating) create special needs, review the sections below — the standard formula has important nuances for athletes, seniors, and people on plant-forward diets. Results are educational estimates and do not replace individualized guidance from a registered dietitian.
Enter your body weight in pounds or kilograms, select your activity level (sedentary through very active), and choose your goal. Tap calculate, and the result shows your recommended daily protein intake as a gram total and as a g/kg ratio. If the result reads "140g/day (2.0 g/kg)," that means eating 140 grams of protein distributed across your meals — roughly 35–45g per main meal plus a snack — hits your target for your stated goal. If the number feels high compared to what you currently eat, close the gap gradually over 1–2 weeks rather than doubling protein overnight, which can cause digestive discomfort.
Protein targets are set as a multiplier of body weight in kilograms:
Protein (g/day) = body weight (kg) × protein factor (g/kg)
Protein factors by goal:
| Goal / Activity Level | Protein Factor (g/kg) |
|---|---|
| Sedentary maintenance | 0.8 |
| Light activity / weight loss | 1.2 – 1.4 |
| Moderate training / muscle maintenance | 1.4 – 1.7 |
| Strength/power athletes | 1.6 – 2.0 |
| Endurance athletes | 1.2 – 1.6 |
For a 75 kg (165 lb) moderately active person targeting muscle maintenance, the target is 75 × 1.6 = 120g protein/day, consistent with USDA AMDR of 10–35% of calories from protein.
If building muscle is the goal, protein needs climb — but probably not as high as gym lore suggests. The research-supported sweet spot for maximizing muscle protein synthesis in resistance-trained individuals is 1.6–2.2 g/kg of body weight, with the upper range of 2.0 g/kg providing a small additional benefit for highly trained lifters. A 180 lb (82 kg) man targeting muscle gain lands at 131–180g protein per day; a 140 lb (64 kg) woman at the same goal needs 102–140g. What matters almost as much as the daily total is distribution: spreading intake across 3–4 meals of 30–40g protein each maximizes the muscle protein synthesis signal because each meal independently activates the response. Back-loading 80% of daily protein into dinner leaves a lot of synthesis potential on the table during the rest of the day.
The USDA RDA of 0.8 g/kg is the minimum to prevent deficiency in sedentary adults — it was never designed as a performance target. Serious endurance athletes need 1.2–1.6 g/kg to offset the amino acid oxidation that occurs during prolonged aerobic work. Strength and power athletes need 1.6–2.0 g/kg to drive hypertrophy. Combat sports athletes cutting weight may need up to 2.3–3.1 g/kg during the cut phase specifically to protect lean mass during aggressive caloric restriction. Beyond absolute quantity, timing matters for athletes: consuming 20–40g protein within two hours post-workout accelerates muscle repair. The practical takeaway is that if you train more than three days per week with any serious intensity, the RDA leaves a significant gap that this calculator accounts for.
Older adults are often the group most quietly underserved by standard protein recommendations. After about age 60, anabolic resistance increases — muscle tissue becomes less sensitive to the protein synthesis signal, meaning older adults need more protein per kilogram to achieve the same anabolic response as younger people. Emerging research, including guidance from organizations like the NIH, suggests that adults over 65 benefit from 1.0–1.2 g/kg at minimum, with some clinicians recommending up to 1.6 g/kg for active seniors to counter sarcopenia (age-related muscle loss). Sarcopenia affects an estimated 10–27% of older adults in the US and is strongly associated with falls, hospitalization, and loss of independence. If you're 65 or older, don't take comfort in a "normal" intake that just clears the 0.8 g/kg RDA — higher targets are both safe and supported.
| Age Group | Protein Needed (grams/day) |
|---|---|
| Children ages 1 – 3 | 13g |
| Children ages 4 – 8 | 19g |
| Children ages 9 – 13 | 34g |
| Girls ages 14 – 18 | 46g |
| Boys ages 14 – 18 | 52g |
| Women ages 19 – 70+ | 46g |
| Men ages 19 – 70+ | 56g |
| Stage | Safe Intake (g/day) | Additional Energy | Protein:Energy Ratio |
|---|---|---|---|
| Pregnancy trimester 1 | 1g | ~375 kJ/day | 0.04 |
| Pregnancy trimester 2 | 10g | ~1,200 kJ/day | 0.11 |
| Pregnancy trimester 3 | 31g | ~1,950 kJ/day | 0.23 |
| Lactation (0–6 months) | 19g | ~2,800 kJ/day | 0.11 |
| Lactation (6+ months) | 13g | ~2,500 kJ/day | 0.11 |
People eating plant-forward or fully vegan diets do need to pay extra attention to protein quantity and quality. Most plant proteins are incomplete — they lack one or more essential amino acids — and are digested less efficiently than animal proteins. The protein digestibility-corrected amino acid score (PDCAAS) for most plant sources runs 10–30% lower than animal sources, which is why some nutrition researchers recommend plant-based eaters target 10–15% higher protein intake than the standard formula suggests. The good news is that complementary proteins (rice + legumes, corn + beans, wheat + peas) across the course of a day cover all essential amino acids without requiring meticulous meal-by-meal pairing. Soy, edamame, lentils, tempeh, and hemp seeds are among the highest-quality plant protein sources. If you're vegan and doing serious resistance training, a target of 1.8–2.2 g/kg accounts for both the bioavailability gap and the training demand.
If possible, consuming a variety of complete proteins is recommended. A complete protein contains a good amount of each of the nine essential amino acids required in the human diet.
| Food | Protein Amount |
|---|---|
| Chicken breast (3 oz, cooked) | 26g |
| Salmon (3 oz, cooked) | 22g |
| Lean ground beef (3 oz, cooked) | 22g |
| Greek yogurt (6 oz, plain nonfat) | 17g |
| Cottage cheese (1/2 cup, low-fat) | 14g |
| Eggs (2 large) | 12g |
| Tofu (1/2 cup, firm) | 10g |
| Lentils (1 cup, cooked) | 18g |
| Protein powder (1 scoop, whey) | 24g |
| Almonds (1 oz, ~23 nuts) | 6g |
For a lot of people, it is — and for some, it's more than enough. Whether 100g meets your target depends entirely on your body weight and goal. For a sedentary 130 lb (59 kg) woman, 100g/day is 1.69 g/kg, which exceeds even the athletic recommendation for her size. For a 200 lb (91 kg) male powerlifter, 100g/day is only 1.1 g/kg — fine for a sedentary adult but well below the 1.6–2.0 g/kg needed to support strength training adaptations. Instead of anchoring on a round number, use your calculated g/kg target, then convert it to grams: it removes the ambiguity and scales correctly for your body.
Body weight is the primary driver of your protein target — heavier individuals have more tissue to maintain and repair. Goal is the second biggest variable: weight loss and muscle gain both push protein targets up (to protect lean mass in a deficit or stimulate synthesis in a surplus), while sedentary maintenance sits at the bare minimum. Training type and volume matter: endurance athletes lose amino acids differently than strength athletes. Age progressively increases the amount of protein needed per kilogram to maintain the same muscle maintenance signal. Dietary pattern affects bioavailability — animal proteins are generally more efficiently absorbed than plant proteins. Finally, health status matters: people with certain kidney conditions may need to limit protein intake, making physician guidance essential before adopting high-protein eating patterns.
Keisha is a 35-year-old in Atlanta, 5'6", 148 lb (67 kg), training for a half marathon (running 4x/week, moderate intensity). Her goal is to maintain weight and performance. Protein target: 67 × 1.5 g/kg = 100g/day. Good sources to hit that: 4 oz chicken breast (35g) + Greek yogurt (17g) + two eggs (12g) + cottage cheese (14g) + protein from whole grains and vegetables across the day (≈22g). Achievable without supplements.
Tyler is a 25-year-old in Phoenix, 6'1", 210 lb (95 kg), competing in natural bodybuilding. Goal: maximize lean muscle during a bulk. Protein target: 95 × 1.9 g/kg = 180g/day. Spread across four meals (45g each): meal one — 6 oz salmon + egg whites (50g), meal two — 8 oz chicken breast (45g), meal three — lean beef stir-fry (45g), meal four — cottage cheese + casein shake (40g). Hitting that total requires deliberate planning but is realistic on a whole-foods diet.
Spread protein across 3–4 meals rather than concentrating it at dinner — each meal independently triggers muscle protein synthesis.
Pair a complete protein source (meat, eggs, dairy, soy) with plant proteins at most meals if you're eating plant-based to cover all essential amino acids.
If you struggle to hit your target from food alone, a whey or plant-based protein shake is a practical bridge — not a requirement, but a convenient tool.
For weight loss, a high protein intake is one of the best levers for appetite control; hitting your target before you drop calories makes the deficit more sustainable.
Seniors should prioritize protein at breakfast — older adults often eat protein-light morning meals, missing an early opportunity for muscle protein synthesis.
Don't fear high protein intakes if your kidneys are healthy — research has not found evidence of kidney damage from high protein in people with normal renal function.
The minimum USDA RDA is 0.8 g per kilogram of body weight for sedentary adults. Active adults and athletes benefit from 1.2–2.0 g/kg depending on training type and intensity, with strength athletes at the higher end.
A 180 lb (82 kg) man aiming for muscle gain should target approximately 131–164g of protein per day — around 1.6–2.0 g/kg. Distributing that across three or four meals maximizes the anabolic signal compared to eating it all at once.
The same g/kg framework applies. A 140 lb (64 kg) woman who exercises regularly needs 77–128g/day depending on whether her goal is maintenance (1.2 g/kg) or muscle gain (2.0 g/kg). Women often undereat protein; this calculator's output is a reliable target.
In healthy individuals with normal kidney function, research has not shown harm from high protein intakes up to 2.2 g/kg or beyond. However, people with existing kidney disease should limit protein per their physician's guidance.
Animal sources — chicken breast, tuna, lean beef, eggs, cottage cheese, Greek yogurt — deliver the most protein per calorie with the best amino acid profile. Plant sources like edamame, lentils, tofu, tempeh, and seitan are strong choices for plant-based eaters.
Yes. Protein is the most satiating macronutrient and has the highest thermic effect (20–30% of its calories are burned during digestion). Higher protein intake during a caloric deficit helps preserve lean muscle, which keeps metabolic rate from dropping as sharply.
Adults over 65 benefit from 1.0–1.6 g/kg to counter anabolic resistance and reduce sarcopenia risk, according to NIH-supported research. That's meaningfully higher than the sedentary adult RDA of 0.8 g/kg.
The USDA Dietary Reference Intakes set the protein RDA at 0.8 grams per kilogram of body weight per day for adults. This is a minimum adequate intake for sedentary adults, not an optimal target for anyone who exercises regularly.
As with everything else, balance is important. Generally, meat, poultry, fish, eggs, and dairy products are complete protein sources. Nuts, seeds, legumes, grains, and vegetables are usually incomplete proteins, but there is nothing wrong with them. As long as you consume a sufficient variety of incomplete proteins to get all the required amino acids, it is not necessary to specifically eat complete protein foods. Consult a dietitian, doctor, or personal trainer to help determine your individual protein needs.
Brief disclaimer: This calculator provides educational protein intake estimates based on body weight, activity level, and goal using USDA Dietary Reference Intakes and published sports nutrition research. Results are starting points for nutrition planning, not clinical prescriptions. Individuals with kidney conditions, metabolic disorders, or other health concerns should consult a physician or registered dietitian before adopting high-protein eating patterns.