Protein is the nutrient people most often under-eat when they train or diet, and the one with the clearest evidence for a target above the bare minimum. This calculator gives a daily range in grams for your weight and goal, then splits it across meals and translates it into real food.
How it is calculated
Targets are set in grams per kilogram of body weight, which is how the research reports them:
- Minimum for healthy adults (RDA): 0.8 g/kg. Enough to avoid deficiency, not optimal for training.
- General fitness: 1.2–1.6 g/kg.
- Building muscle: 1.6–2.2 g/kg. Meta-analyses find gains plateau around 1.6 g/kg for most people; going higher costs nothing but has a small extra effect.
- Losing fat while keeping muscle: 1.8–2.4 g/kg. Higher protein in a deficit preserves lean mass and reduces hunger.
- Age 65 and over: 1.0–1.2 g/kg to counter age-related muscle loss.
- Pregnancy: about 1.1–1.3 g/kg in the second and third trimesters.
The calculator shows the middle of the range as the main number and the full range under it. For lean people the numbers are accurate as-is. For people carrying a lot of extra weight, using goal weight instead of current weight avoids overshooting.
Example
A 75 kg person training three times a week to build muscle: 75 × 1.6–2.2 = 120–165 g a day, about 140 g in the middle. Over four meals that is about 35 g each, roughly a chicken breast, a large serving of Greek yogurt or a scoop of whey with milk.
Does timing matter?
Less than total intake, but somewhat. Spreading protein into 3–5 servings of 25–40 g gives more muscle protein synthesis than the same total in one or two meals, and a serving within a few hours of training helps. The "anabolic window" of 30 minutes is a myth; the day matters, not the minute.
Frequently asked questions
How much protein do I need to build muscle?
About 1.6–2.2 g per kilogram of body weight per day. Research shows most of the benefit by 1.6 g/kg; higher intakes add a little more and help if you are also in a deficit.
Is too much protein bad for your kidneys?
Not for healthy kidneys. Studies up to about 3 g/kg in healthy adults show no harm. People with existing kidney disease should follow their doctor’s limits.
Should I calculate protein from lean mass or total weight?
Total weight works for most people. If your BMI is over 30, use your goal weight or lean mass, otherwise the target overshoots what your muscle mass can use.
How much protein per meal can the body absorb?
The body absorbs almost all of it; the old "30 g limit" refers to how much muscle protein synthesis is stimulated per serving. Servings of 25–40 g are a practical sweet spot, and larger meals are not wasted, just used more slowly.
Do I need protein powder?
No. Powder is a convenient, cheap source, not a requirement. If you hit your target from meat, dairy, eggs, legumes and soy, there is no extra benefit from supplements.
Sources
- Morton RW et al. A systematic review, meta-analysis and meta-regression of protein supplementation on resistance training-induced gains. Br J Sports Med, 2018
- Jäger R et al. International Society of Sports Nutrition position stand: protein and exercise. JISSN, 2017
- Bauer J et al. Evidence-based recommendations for optimal dietary protein intake in older people (PROT-AGE). JAMDA, 2013
- Dietary Reference Intakes for Macronutrients. National Academies, 2005
By Calcelate Team. Formula from the sources above.
- 2026-09-14 · Formula and texts checked