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Protein calculator: how much protein per day

Short answer

To build muscle with resistance training, research points to about 1.6 g of protein per kg of body weight per day, with little extra benefit beyond that on average; the International Society of Sports Nutrition recommends 1.4–2.0 g/kg for most exercising people. The general adult RDA is 0.8 g/kg. For an 80 kg (176 lb) person, that is about 130 g a day.

Last reviewed 12 October 20262 published sourcesNot medical advice

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Daily protein calculator

Based on your current body weight.

kg
Unit

To build muscle

122 g/day

1.6 g/kg · Morton et al.

ISSN range

105–150 g

1.4–2.0 g/kg per day

Per meal

≈ 19 g

0.25 g/kg · or 20–40 g

At 75 kg, the adult RDA of 0.8 g/kg works out to 60 g a day. For muscle gain with resistance training, the meta-analysis breakpoint is about 122 g, and the upper end of its confidence interval (2.2 g/kg) is 165 g.

How much protein per day to build muscle

A 2018 meta-analysis of 49 studies with 1,863 participants found that protein supplementation boosted gains in muscle mass and strength from resistance training, and that the gains in fat-free mass plateaued at a total intake of about 1.62 g per kg of body weight per day (95% confidence interval 1.03–2.20) (Morton et al., 2018). The International Society of Sports Nutrition recommends 1.4–2.0 g/kg per day as sufficient for most exercising people (Jäger et al., 2017 (ISSN)).

Daily protein by body weight (grams per day)
Body weightRDA 0.8 g/kgISSN 1.4–2.0 g/kg1.6 g/kg
50 kg (110 lb)40 g70–100 g81 g
60 kg (132 lb)48 g84–120 g97 g
70 kg (154 lb)56 g98–140 g113 g
80 kg (176 lb)64 g112–160 g130 g
90 kg (198 lb)72 g126–180 g146 g
100 kg (220 lb)80 g140–200 g162 g
110 kg (243 lb)88 g154–220 g178 g
Rounded to the nearest gram. 1.6 g/kg is the Morton et al. breakpoint (1.62 g/kg).

Is the RDA enough?

The US and Canadian RDA is 0.8 g/kg per day. Morton et al. concluded that this amount appears insufficient for people whose goal is to gain strength and muscle with resistance training, particularly older adults (Morton et al., 2018). They also found supplementation was less effective with increasing age and more effective in people who were already resistance trained.

Spreading protein across the day

The ISSN suggests about 0.25 g/kg of high-quality protein per meal, or an absolute 20–40 g, ideally spread evenly every 3–4 hours (Jäger et al., 2017 (ISSN)). People with kidney disease or other medical conditions should agree protein targets with their clinician.

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Common questions

How much protein do I need to build muscle?

Morton et al.'s 2018 meta-analysis of 49 studies found muscle gains from resistance training plateaued at about 1.62 g of protein per kg of body weight per day (95% confidence interval 1.03–2.20). The ISSN recommends 1.4–2.0 g/kg per day for most exercising people.

Is 0.8 g/kg of protein enough?

0.8 g/kg per day is the US and Canadian RDA for adults. Morton et al. concluded it appears insufficient for people aiming to gain strength and muscle with resistance training.

How much protein per meal?

The ISSN position stand suggests about 0.25 g/kg of high-quality protein per meal, or an absolute 20–40 g, ideally spread every 3–4 hours across the day.

Sources

Figures on this page were checked against these publications on 12 October 2026.

  1. Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. British Journal of Sports Medicine. 2018;52(6):376–384. doi.org/10.1136/bjsports-2017-097608
  2. Jäger R, Kerksick CM, Campbell BI, Cribb PJ, Wells SD, Skwiat TM, et al. International Society of Sports Nutrition position stand: protein and exercise. Journal of the International Society of Sports Nutrition. 2017;14:20. doi.org/10.1186/s12970-017-0177-8

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