Protein Intake Calculator
Estimate how much protein to eat each day, in grams, based on your body weight and your goal — from general health to building muscle or losing fat while keeping it.
Why protein matters
Protein is the macronutrient your body uses to build and repair tissue — muscle, skin, hair, enzymes, hormones and immune cells. Unlike fat and (to a degree) carbohydrate, the body does not store a reserve of spare protein, so a steady daily supply keeps repair and maintenance running smoothly. Getting enough is one of the highest-impact diet habits for most people: it supports muscle building and recovery from exercise, helps you feel full so you eat less without trying, and becomes increasingly important with age to slow the natural loss of muscle (sarcopenia).
How much you need depends mainly on your body weight and how active you are, which is why this calculator works from grams per kilogram (or pound) of body weight rather than a one-size-fits-all number.
How to use this calculator
Enter your weight in your preferred units and choose the goal or activity level that best describes you — from general health to regular training or actively building muscle. The calculator multiplies your weight by an appropriate grams-per-kilogram range and returns a daily protein target, often with a rough per-meal amount so you can spread intake sensibly across the day.
How it's calculated
The method is simple: daily protein (grams) = your body weight × a grams-per-kilogram factor chosen for your goal. The official baseline to prevent deficiency, the RDA, is about 0.8 g/kg for sedentary adults — but that is a minimum to avoid shortfall, not an optimum for active people. Those who exercise regularly generally do better around 1.2–1.6 g/kg, and people doing serious strength or endurance training, or dieting to lose fat while keeping muscle, are commonly advised to aim for 1.6–2.2 g/kg. Older adults often benefit from the higher end of the general range to counter age-related muscle loss. If you weigh in pounds, divide by 2.2 to convert to kilograms first.
Spreading protein across the day helps too. Muscle protein synthesis responds best to roughly 20–40 g of quality protein per meal, so three to four protein-containing meals tend to support recovery better than one very large serving.
Worked example
A 70 kg recreational lifter aiming to build muscle might target the upper range — say 1.8 g/kg. That is 70 × 1.8 = 126 g of protein a day. Split across four meals, that is roughly 30–32 g each: for instance a chicken breast, a serving of Greek yogurt, a scoop of whey, and a portion of beans or eggs.
| Profile | Protein (g/kg) | Example: 70 kg person |
|---|---|---|
| Sedentary adult (RDA minimum) | 0.8 | ~56 g/day |
| General health / lightly active | 1.0–1.2 | ~70–84 g/day |
| Regular exerciser | 1.2–1.6 | ~84–112 g/day |
| Building muscle / fat loss | 1.6–2.2 | ~112–154 g/day |
| Older adult (preserving muscle) | 1.2–1.6 | ~84–112 g/day |
Limitations & tips
Not all protein sources are equal. Complete proteins — meat, fish, eggs, dairy, soy and quinoa — contain all the essential amino acids your body cannot make. Most plant proteins are "incomplete," but eating a variety across the day (beans with grains, for example) easily covers the full set, so vegetarians and vegans can meet their needs with a little planning. For healthy people, intakes up to around 2 g/kg are well tolerated and very high amounts simply offer little extra benefit. These are general estimates, not medical advice: if you have kidney disease or another condition that affects how your body handles protein, check with your doctor or a registered dietitian before raising your intake significantly.
Frequently asked questions
How much protein do I need per day?
It depends on weight and activity. General health is around 0.8 g per kg of body weight; active people and those building muscle do better at 1.6–2.2 g/kg. The calculator gives a range and a midpoint for your goal.
Should I count protein per kilogram or per pound?
Research uses grams per kilogram of body weight. If you weigh in pounds, the calculator converts for you — just enter your weight in whichever units you prefer.
Can I eat too much protein?
For healthy people, intakes up to about 2 g/kg are well tolerated. Very high intakes offer little extra benefit for most goals. If you have kidney disease, check with your doctor before raising protein significantly.
How much protein can my body use in one meal?
Muscle protein synthesis is stimulated well by roughly 20–40 g of quality protein per meal. Larger amounts still get used for other purposes and aren't "wasted," but for muscle gain it's more effective to spread protein across three or four meals than to load it all at once.
What are the best protein sources?
Complete sources — meat, poultry, fish, eggs, dairy, soy and quinoa — supply all essential amino acids. Most plant foods are incomplete on their own, but combining varieties such as beans with grains over the day covers everything, so balanced vegetarian and vegan diets meet protein needs well.
Do I need protein right after a workout?
The old "anabolic window" of 30 minutes is now considered much wider — what matters most is your total daily protein. Having a protein-containing meal within a few hours of training is plenty; you don't need to rush a shake the moment you finish.
Sources & references
- National Academies (Institute of Medicine) — Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids — source of the 0.8 g/kg RDA for protein used as this calculator's baseline.
- International Society of Sports Nutrition — Position Stand: Protein and Exercise — supports the higher 1.4–2.0+ g/kg/day ranges this tool suggests for exercising individuals.
Last updated: July 2026 · How we calculate
BriskToolbox provides estimates for general information only and is not medical advice. Talk to a healthcare professional about your individual health.