Protein is the lever most people under-set when they change body composition. The U.S. Recommended Dietary Allowance of 0.8 grams per kilogram of body weight is a deficiency floor for sedentary adults, not a training target. Sports-nutrition position stands from the International Society of Sports Nutrition (ISSN) and the American College of Sports Medicine (ACSM) cluster practical intakes around 1.6 g/kg for people who lift or do mixed training, about 2.0 g/kg when you are in a calorie deficit and want to keep lean mass, and up to 2.2 g/kg for lean athletes cutting hard. This calculator multiplies your body weight by the goal you pick so you can see grams per day, then split that total across meals instead of trying to swallow it in one sitting. A 70 kg adult at 0.8 g/kg needs 56 g — easy to hit with a mixed diet. The same person at 1.6 g/kg needs 112 g; at 2.0 g/kg, 140 g; at 2.2 g/kg, 154 g. Spreading 25–40 g across three to five eating occasions usually beats one 80 g dinner for satiety and for hitting a leucine threshold that supports muscle protein synthesis. Plant-forward eaters can hit the same totals, but they should plan complementary proteins — legumes plus grains, tofu plus grains — and check that a few meals actually deliver leucine, not only bulk grams. This page is an educational estimate, not medical advice. Kidney disease, pregnancy, eating disorders, and prescribed diets need a clinician, not a browser widget. If you want the activity side of the same picture — steps, workouts, and whether your days actually look active — StepDay reads Apple Health so your protein target is not floating next to a guessed lifestyle.
Pick the g/kg that matches the goal, convert to grams, then split across meals. Recheck when weight or the deficit changes.
Use 0.8 g/kg only as the sedentary minimum if you do not train and are not trying to change composition. Pick 1.6 g/kg as the default ISSN-style training intake. Move to 2.0 g/kg when calories drop and you want to protect muscle. Reserve 2.2 g/kg for lean athletes in a hard cut, then confirm you can actually chew that much food. The calculator shows the 70 kg column so you can sanity-check the math before you shop.
Divide the total by three to five eating occasions. A 140 g day is four meals of 35 g, not one 140 g shake at 10 p.m. Most people absorb and use protein better when each sitting lands in the 25–40 g range, which is also easier on appetite and on the grocery list. If you skip breakfast, put a protein-dense lunch and a second afternoon meal on the calendar instead of hoping dinner will carry the whole target.
Tofu, tempeh, lentils, seitan, and Greek-style soy yogurt can hit the gram target, but single plant foods are often lower in leucine than chicken or whey. Pair legumes with grains or seeds in the same day, and put a leucine-rich item (tofu, tempeh, seitan, or a fortified soy yogurt) in at least two meals. Track cooked weights, not package slogans: 100 g cooked lentils is closer to 9 g protein than to a steak. If dairy and eggs are on the table, they are the easiest bridges.
This is not a prescription and not a diagnosis. If you have kidney disease, are pregnant, have a history of disordered eating, or follow a clinician-set diet, stop here and ask that clinician before raising protein. For everyone else, hold the target for two to three weeks, watch satiety, training quality, and the scale trend, then nudge by 0.2 g/kg rather than jumping from 0.8 to 2.2 overnight. Pair the grams with a TDEE or BMR check so the calories around the protein still make sense.
Formulas, reference tables, and practical guidance you can come back to.
The four anchors below are the ones you will see in ISSN- and ACSM-adjacent popular summaries: 0.8 g/kg as the sedentary RDA-style floor, 1.6 g/kg as the default training intake, 2.0 g/kg when you are losing fat and want a higher fraction of each calorie to be amino acids, and 2.2 g/kg as a practical ceiling for lean athletes in a hard deficit. They are not personalized prescriptions. A 90 kg novice who walks a lot and lifts three days a week is not the same human as a 60 kg physique athlete in week six of a cut, even if both type “1.6” into a form. Use the 70 kg column as a sanity check: if your weight is 80 kg, scale the grams by 80/70. If your weight is 55 kg, scale down the same way. The calculator does that multiplication for the weight you enter; the table exists so search snippets and humans can quote a shared example without inventing new arithmetic.
Read the grams as food, not as a powder tax. 112 g at 1.6 g/kg for 70 kg is two 150 g cooked chicken breasts plus a large Greek yogurt, or a tofu-heavy day plus lentils, not a moral failing if you miss by 10 g. People who jump from 0.8 to 2.2 in one grocery trip usually fail the chew test and bounce back to toast. Hold a target for two to three weeks, watch training quality and the weekly weight average, then move 0.2 g/kg. Pair this table with a TDEE check: high protein inside a huge surplus still stores fat, and high protein inside a crash deficit still feels miserable if total calories are fiction. Educational use only — not medical advice.
| Goal | g/kg | 70 kg example |
|---|---|---|
| Sedentary minimum (RDA-style) | 0.8 | 56 g/day |
| General training (ISSN midpoint) | 1.6 | 112 g/day |
| Fat loss / keep lean mass | 2.0 | 140 g/day |
| Lean athlete, hard deficit | 2.2 | 154 g/day |
Grams per kilogram only become useful when they turn into a plate. The serving sizes below are the ones people actually buy: 100 g cooked chicken breast, one large egg, a 170 g (6 oz) cup of Greek yogurt, 100 g firm tofu, and 100 g cooked lentils. Numbers are typical USDA-style averages, not a lab assay of the package in your fridge. Skin-on chicken, silken tofu, and flavored yogurt will move the decimal. Use the table to build two or three default meals, then repeat them. Variety is optional; hitting the daily total is not. If you eat out, assume restaurant chicken is closer to 80–100 g cooked meat than to the 200 g you imagine, and log honestly for a week before you decide the calculator is “wrong.”
A 70 kg athlete at 1.6 g/kg (112 g) can build a day from 200 g cooked chicken (~62 g), two eggs (~13 g), 170 g Greek yogurt (~17 g), and still need a fourth sitting — tofu, lentils, or another yogurt — to close the gap. That is why “I eat chicken at dinner” rarely equals 2.0 g/kg. Vegetarians swapping the chicken for 300 g firm tofu (~45–51 g depending on brand water) plus a cup of lentils and yogurt can land in the same band if they stop treating a side salad as protein. Seitan is denser than tofu; silken tofu is not. Weigh cooked food for seven days once, then you can eyeball. Again: educational, not a diet prescription and not medical advice.
| Food | Serving | Protein (typical) |
|---|---|---|
| Chicken breast, cooked | 100 g | ~31 g |
| Egg, large | 1 egg | ~6.3 g |
| Greek yogurt, plain | 170 g (6 oz) | ~15–17 g |
| Firm tofu | 100 g | ~15–17 g |
| Lentils, cooked | 100 g | ~9 g |
Once you have a daily gram number, the operational question is how many times you will chew. Research on muscle protein synthesis in adults repeatedly shows a per-meal leucine trigger in the neighborhood of 2–3 g leucine, which maps to roughly 25–40 g of high-quality protein for most mixed meals. That is why this page refuses the “one 80 g dinner plus cereal” pattern. A four-meal template for 140 g (70 kg at 2.0 g/kg) is 35 g at breakfast, 35 g at lunch, 35 g pre- or post-training, and 35 g at dinner. A three-meal template is about 45 g × 3, which is still workable if you tolerate larger sittings. Snacks count if they are yogurt, tofu, or lentils — not if they are crackers with a protein halo on the box.
The medical boundary is sharp on purpose. High protein eating is widely used in healthy training adults; it is not automatically safe in chronic kidney disease, in some metabolic conditions, during pregnancy without a clinician, or in active eating-disorder treatment. This calculator will not ask about creatinine, medications, or psychiatric history, which is exactly why it must not be treated as care. If a doctor, dietitian, or treatment team has set a protein cap or floor, their number overrides every cell in these tables. Everyone else can treat 1.6 g/kg as a default experiment for two to three weeks, drink enough water (see the water-intake and steps reading links), and let StepDay show whether daily movement matches the “I train hard” story that justified 2.2 g/kg in the first place.
| Template | Meals | Per meal (70 kg @ 2.0) |
|---|---|---|
| Four-meal day | 4 | 35 g |
| Three-meal day | 3 | ~47 g |
| Five-meal day | 5 | 28 g |
| Medical override | Clinician | Their cap/floor wins |
Quick answers about this tool and how to train with it.
Usually no. 0.8 g/kg is the RDA-style minimum meant to prevent deficiency in sedentary adults, not to support hypertrophy or hard endurance blocks. ISSN reviews commonly land exercising people at roughly 1.4–2.0 g/kg, with 1.6 g/kg a practical midpoint. If you lift three or more days a week, start at 1.6 and only drop toward 0.8 if a clinician has a medical reason. Eating at the floor while you add training volume is how people lose strength and call it a mysterious plateau.
Those numbers are clustered around published position stands, not a single magic meal. 1.6 g/kg sits in the middle of the range that reliably supports training adaptations for most recreational lifters and mixed athletes. 2.0 g/kg shows up when energy intake falls — more of each calorie needs to be protein if you still want net muscle protein balance. 2.2 g/kg is the upper practical band for very lean athletes in a deficit; going higher rarely buys more muscle and just crowds out carbs you need for the work. This tool maps those four common anchors so you can compare them on the same body weight.
Aim for three to five feedings of about 25–40 g rather than one huge dinner. That pattern is easier to chew, easier to shop, and closer to the per-meal leucine dose that repeatedly triggers muscle protein synthesis in adult research. A 112 g day (70 kg at 1.6 g/kg) is four meals near 28 g or three meals near 37 g. If you train in the afternoon, put one of those servings in the meal before and the meal after the session. Overnight fasting is normal; you do not need a 3 a.m. casein shake unless a dietitian put it there.
Yes, if you plan complementary proteins and accept a larger plate. Firm tofu, tempeh, seitan, lentils, and Greek-style soy yogurt are the dense options; white rice or a plain salad will not get you there. Because many plant proteins are lower in leucine, some plant-forward athletes sit 10–20% above the animal-diet gram target or add a fortified soy product at two meals. Cooked-weight logging matters: 100 g firm tofu is in a different league from 100 g cooked lentils. This is still not medical advice — B12, iron, and energy availability stay on the checklist with a clinician if you restrict food groups.
No. The calculator is a sports-nutrition education widget that applies publicly discussed ISSN/ACSM-style anchors (0.8 / 1.6 / 2.0 / 2.2 g/kg) to the weight you enter. It does not know your labs, medications, kidney function, or pregnancy status. Do not use it to self-treat illness, to push protein during an eating-disorder recovery, or to override a registered dietitian. If anything here conflicts with a clinician, the clinician wins. For daily movement context around the same calories, StepDay can show whether your step and workout week actually matches the “active” story you told the protein math.
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