Protein Intake Calculator for Muscle Gain
Protein intake calculator for muscle gain: your daily target in grams for building, maintaining or cutting, split into meals and backed by the research.
Protein covered and still not growing? Find the real bottleneck.
| Meals a day | Protein each |
|---|---|
| 3 | 44 g |
| 4 | 33 g |
| 5 | 26 g |
Schoenfeld and Aragon suggest about 0.4 g/kg per meal over at least four meals, up to 0.55 g/kg.
The target, 1.6 g/kg, is where extra protein stopped adding muscle in Morton et al.'s meta-analysis of 49 trials. The top of the range, 2.2 g/kg, is what the same authors suggest for anyone trying to squeeze out every last gram.
Sources: Morton et al. 2018, Br J Sports Med; Jäger et al. 2017, ISSN position stand: protein and exercise; Helms et al. 2014, Int J Sport Nutr Exerc Metab; Schoenfeld & Aragon 2018, J Int Soc Sports Nutr.
Numbers not moving for weeks? Find out why- Updated
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This protein intake calculator gives you a daily protein target in grams for your goal and splits it across your meals. For building muscle the target is 1.6 g per kg of bodyweight a day (0.73 g per lb), with a useful range up to 2.2 g/kg. On a cut it rises to 2.3–3.1 g per kg of lean mass. Hit the target every day before you worry about anything fancier.
How do you use the protein intake calculator?
Enter your bodyweight, pick your goal and, if you are cutting and know it, add your body fat percentage. The calculator returns a daily target, a range and the grams per meal for three to five meals.
- Building muscle or recomping: choose "build".
- Holding your size while training: choose "maintain".
- Losing fat: choose "cut" and add body fat, so the target is based on lean mass instead of total weight.
How much protein does the calculator recommend?
For an 82 kg (180 lb) lifter, the targets work out like this.
| Goal | Guideline | Daily protein at 82 kg |
|---|---|---|
| Build muscle | 1.6–2.2 g/kg | 131–180 g |
| Maintain | 1.4–2.0 g/kg | 115–164 g |
| Cut, 15% body fat | 2.3–3.1 g/kg of lean mass | 160–216 g |
The build range comes from a meta-analysis of 49 trials and 1,863 people: gains in fat-free mass stopped improving at 1.62 g/kg a day, with a 95% confidence interval of 1.03–2.20 (Morton et al., 2018). The maintain range is the ISSN's 1.4–2.0 g/kg for most exercising people (Jäger et al., 2017). The cut range is 2.3–3.1 g/kg of fat-free mass, higher the leaner you are and the harder you diet (Helms et al., 2014).
Why does the target stop at 1.6 g/kg?
Because that is where extra protein stopped adding muscle in the research, on average. Eating 2.2 g/kg is a safety margin for people at the top of the interval, not a requirement. LiftDecode's rule: hit 1.6 every day for a month before you consider going higher.
How should you split protein across meals?
Aim for about 0.4 g/kg per meal across at least four meals, or up to 0.55 g/kg if you eat at the top of the range (Schoenfeld & Aragon, 2018). At 82 kg that is 33–45 g a meal.
Older lifters need bigger doses: men in their seventies needed about 0.40 g/kg in one meal to max out muscle building, younger men about 0.24 g/kg (Moore et al., 2015). Large meals are not wasted either. A 100 g dose kept muscle building elevated for more than 12 hours, far longer than 25 g (Trommelen et al., 2023). Details by meal count are in how much protein per meal.
What if you hit your protein and still don't grow?
Then protein is not your bottleneck, and adding more will not fix it.
Its effect is real but modest: in the same meta-analysis, extra protein added about 0.30 kg of fat-free mass over a training program (Morton et al., 2018). The usual culprits are sets that stop too early, no progression, too little weekly volume, not enough total food or short sleep. Find out which one is holding you back, or check the evidence in how much protein to build muscle.
FAQ
How do I calculate how much protein I need?
Multiply your bodyweight in kg by 1.6 for building muscle, or your weight in lb by 0.73. A 180 lb lifter needs about 131 g a day; up to 180 g is still useful but rarely necessary.
How much protein does a 150 lb woman need to build muscle?
About 109 g a day (68 kg × 1.6), with 150 g as the upper useful amount. The guideline is per kilogram of bodyweight, so the same calculation applies to women.
Is 100 g of protein a day enough?
For building muscle, 100 g covers lifters up to about 62 kg (138 lb). Heavier lifters need more: 1.6 g per kg is the target the research supports.
Do I need more protein as I get older?
Per meal, yes. Older muscle needs a bigger dose to respond, so put 0.4 g/kg or more into each meal instead of spreading small snacks through the day.
Written and maintained by LiftDecode. Training and nutrition education for healthy adults, not medical advice — if you have a health condition or an injury, talk to a professional who can examine you.