Protein calculator

How much protein do you actually need a day? It depends on your body weight, how active you are and what you're aiming for. Enter your weight and goal to get a daily range in grams, plus how much that is per meal.

Where these numbers come from

The official minimum (RDA) is 0.8 g per kg of body weight a day. That's enough to avoid deficiency in sedentary adults, not a target for anyone training or trying to keep muscle while losing fat.

For building muscle, the largest meta-analysis to date (Morton and colleagues, 2018, 49 trials) found that the benefit of extra protein levelled off around 1.6 g/kg a day, with an upper confidence limit of about 2.2 g/kg. That's why the 'build muscle' range for regular lifters is 1.6–2.2 g/kg.

When you eat less to lose fat, protein helps protect muscle. The International Society of Sports Nutrition suggests higher intakes during a calorie deficit for people who train, which is why the 'lose fat' range goes up to 2.4 g/kg.

Total protein matters more than timing

Spreading protein over three or four meals of roughly 0.3–0.4 g/kg each is a sensible pattern, but research comparing before- and after-workout protein finds little difference when the daily total is the same. Hit the daily number first; fine-tune timing later.

Good sources: eggs, dairy and Greek yoghurt, fish, poultry, lean meat, tofu and tempeh, legumes, and protein powder when food is inconvenient.

Turn the number into meals

Trainr builds a meal plan around your protein and calorie targets, logs meals from a photo, and shows in your body scans whether the change is fat or muscle. The first scan is free.

Get your plan — start free

Common questions

How much protein do I need to build muscle?

For people lifting regularly, about 1.6 g per kg of body weight a day captures most of the benefit, and up to 2.2 g/kg covers those who respond best (Morton et al., 2018).

How much protein do I need to lose weight?

Around 1.2–1.6 g/kg if you're active, and 1.6–2.4 g/kg if you strength train while in a deficit, to help keep muscle while the fat comes off.

Is too much protein bad for you?

For healthy adults, intakes up to about 2 g/kg are well studied and considered safe. People with kidney disease should follow their doctor's advice.

Should I use my current weight or goal weight?

If you're lean or average, current weight is fine. If you carry a lot of extra fat, use a realistic goal weight — protein needs follow lean mass.

Hit your daily protein range consistently, and let your measurements tell you whether it's working.

Sources

Morton RW, Murphy KT, McKellar SR, et al. (2018). 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. https://pmc.ncbi.nlm.nih.gov/articles/PMC5867436/
Aragon AA, Schoenfeld BJ, Wildman R, et al. (2017). International Society of Sports Nutrition position stand: diets and body composition. Journal of the International Society of Sports Nutrition. https://pubmed.ncbi.nlm.nih.gov/28630601/

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Trainr is a wellness tool, not a medical device. These calculators give estimates for self-tracking, not a diagnosis. For medical questions, talk to a professional.