Protein Intake Calculator: How Much Protein Do You Need?

How much protein to build muscle (grams per kg)

The International Society of Sports Nutrition’s position stand recommends 1.4–2.0 g of protein per kg of body weight per day for people doing regular resistance training, spread over 3–4 meals with roughly 0.25–0.4 g/kg per meal. For an 80 kg lifter that is about 110–160 g a day. Going above 2.2 g/kg has no extra muscle-building effect in the evidence so far.

Protein for weight loss

During a calorie deficit, protein protects muscle and keeps you full. Intakes toward the upper end of the range (about 1.6–2.4 g/kg of body weight) are used in weight-loss studies for that reason. If you carry a lot of excess weight, calculate from your goal weight rather than current weight so the number stays realistic.

Protein needs for women

The formulas are the same for women and men — protein needs scale with body weight and activity, not sex. The RDA of 0.8 g/kg (about 46 g for a 58 kg woman) is a minimum to prevent deficiency, not an optimum for training. Pregnancy and breastfeeding raise needs; a clinician should set those targets.

Protein per kg by goal (table)

Goal	g per kg body weight	70 kg person
minimum (RDA, sedentary)	0.8	56 g
general health, active	1.2 – 1.6	84 – 112 g
muscle gain (resistance training)	1.4 – 2.0	98 – 140 g
fat loss while keeping muscle	1.6 – 2.4	112 – 168 g

Sources

• Jäger R et al., ISSN Position Stand: protein and exercise, J Int Soc Sports Nutr 2017 (PubMed 28642676) — https://pubmed.ncbi.nlm.nih.gov/28642676/
• Harvard T.H. Chan Nutrition Source, Protein (RDA 0.8 g/kg) — https://nutritionsource.hsph.harvard.edu/what-should-you-eat/protein/
• NIH, DRI summary table (RDA/AI) — https://www.ncbi.nlm.nih.gov/books/NBK56068/table/summarytables.t4/

This calculator is educational and not medical advice. If you have a health condition, are pregnant, or are under 18, ask a clinician before changing your diet.