How to use this calculator
- Enter or choose body weight.
- Enter or choose unit.
- Enter or choose recommendation.
- Enter or choose meals per day.
- The daily protein updates as you type. Use Copy result or Share to keep it.
Method
Protein (g/day) = body weight (kg) × g/kg; RDA = 0.8 g/kg; ISSN = 1.4–2.0 g/kg; per meal = 0.25 g/kg
- body weight
- in kg (1 lb = 0.45359237 kg)
- g/kg
- grams of protein per kilogram of body weight per day
Worked example
- Lower: 80 × 1.4 = 112 g; upper: 80 × 2.0 = 160 g.
- RDA for comparison: 80 × 0.8 = 64 g.
- ISSN per-meal dose: 80 × 0.25 = 20 g.
An 80 kg person who trains regularly would aim for about 112–160 g of protein a day, roughly 20–40 g per meal.
What the result means
Use the range as a daily target averaged over the week, spread across meals. The RDA covers basic needs for most healthy adults; higher intakes mainly help people doing resistance or endurance training.
Assumptions and limits
- You are a healthy adult (the RDA of 0.8 g/kg applies to adults).
- Body weight is a reasonable proxy for lean mass; at high body fat, using a goal or lean-mass weight may be more appropriate.
- Not for people with kidney disease, who may need protein restriction, or for pregnancy, breastfeeding or children, whose needs differ.
- The ISSN range comes from studies of exercising people; it is not a requirement for sedentary adults.
Questions
Is 0.8 g/kg enough?
It meets the basic needs of most healthy adults and is best read as a minimum rather than an optimum. People who train regularly are usually advised more.
Should I eat more than 2 g/kg?
The ISSN says 1.4–2.0 g/kg is sufficient for most exercising people, and notes that intakes above 3 g/kg may help body composition in resistance-trained individuals. Anyone with kidney disease should follow medical advice instead.
Sources
Please note: This is a general screening estimate for adults, not medical advice or a diagnosis. Talk to a qualified health professional about your health.