Protein calculator

Work out how many grams of protein to eat per day for your weight and goal, from the 0.8 g/kg RDA to 1.6–2.2 g/kg for building muscle, with a per-meal target.

Where the ranges come from

Goal	g per kg per day	Basis
Minimum for health	0.8	U.S. RDA for adults
Active, general fitness	1.2–1.6	Sports-nutrition position stands
Losing weight, keeping muscle	1.2–1.6	Higher protein supports muscle retention in a deficit
Building muscle	1.6–2.2	Morton et al. 2018: gains plateau around 1.6, upper bound ~2.2

The 2018 meta-analysis by Morton and colleagues pooled 49 trials of resistance training with protein supplementation and found that extra protein stopped adding muscle at around 1.6 g per kg of body weight per day, with the upper confidence limit near 2.2 g/kg. That is why the muscle-building range here stops at 2.2.

Making the number easy to hit

Build each meal around a protein source: eggs, Greek yogurt, fish, chicken, tofu, lentils.
Split the day's target over three or four meals of roughly 20–40 g.
Track for a week; most people find they are short at breakfast.

Greek yogurt, sliced chicken, lentils, eggs, tofu and a glass of milk on a stone surface — Common protein sources. A tracker that shows protein per meal makes the gaps obvious.

Questions

How much protein do I need per day?

The adult RDA is 0.8 g per kg of body weight, the minimum to avoid deficiency. Active people and people losing weight usually do better around 1.2–1.6 g/kg, and people building muscle with resistance training around 1.6 g/kg, with benefits plateauing up to about 2.2 g/kg.

Can you eat too much protein?

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

Should I spread protein across meals?

It helps. Many sports-nutrition guidelines suggest roughly 20–40 g of protein per meal spread over the day rather than one large serving.

Do I use my current weight or goal weight?

If you are carrying a lot of extra weight, using your goal weight (or a weight in the healthy range) gives a more sensible target, because protein needs track lean mass more than total mass.

Sources

Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. 2005 (RDA 0.8 g/kg).
Morton RW, Murphy KT, McKellar SR, 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. Br J Sports Med. 2018;52(6):376–384.
Jäger R, Kerksick CM, Campbell BI, et al. International Society of Sports Nutrition position stand: protein and exercise. J Int Soc Sports Nutr. 2017;14:20.

Built and checked by Ingrid Solberg. Last reviewed October 22, 2026. All formulas: formulas & sources.