Planning estimates for healthy adults, not medical advice.
TL;DR
Aim for 0.7 to 1.0 grams of protein per pound of body weight per day to build muscle, 0.8 to 1.2 to keep muscle while cutting, and 0.6 to 0.8 to maintain. For a 180 lb lifter chasing growth, that is 126 to 180 grams spread over 3 to 5 meals.
THE METHOD
HOW THE FORGE measures.
The tool multiplies your body weight by a per-pound protein range that depends on your goal: 0.7 to 1.0 grams per pound to build muscle, 0.8 to 1.2 while cutting, 0.6 to 0.8 to maintain. The muscle-building band is anchored on Morton et al. 2018, a systematic review and meta-analysis in the British Journal of Sports Medicine (PMID 28698222) covering 49 studies and 1,863 people training with weights. It found protein improved gains in lean mass up to roughly 1.6 grams per kilogram of body weight per day, about 0.73 grams per pound, with the upper end of the confidence interval near 2.2 grams per kilogram, about 1 gram per pound.
Two honest caveats. The numbers are meta-analysis averages: the plateau point differs from person to person, which is exactly why the tool gives you a band instead of a single decree. And the cut and maintenance bands are practical extensions coaches build around that same research; a calorie deficit puts muscle at risk, and holding protein at the high end is the standard defense. Treat every number here as a working range, not a law.
You will also see protein advice given as a percentage of daily calories. We skip that on purpose: your muscle does not scale with your food intake. On a deep cut, a percentage target shrinks exactly when protein matters most, while a body-weight target holds steady. If you think in metric, the build band works out to roughly 1.5 to 2.2 grams per kilogram; the toggle just changes what you type. We also keep the inputs to weight and goal on purpose: training age and frequency shift the exact optimum far less than total intake does, and a tool that asks ten questions to move the answer by five grams is theater.
THE BANDS
BUILD MUSCLE
0.7 to 1.0 g / lb
LOSE FAT, KEEP MUSCLE
0.8 to 1.2 g / lb
MAINTAIN
0.6 to 0.8 g / lb
Morton et al., 2018 · 49 studies · 1,863 lifters
NOTHING BUILDS WITHOUT material.
THE WORK
PUT THE MATERIAL TO work.
Pick one number inside your band and hold it for a month. The low end already covers most of the benefit; the high end buys insurance during a cut, when the deficit is working against your muscle. Landing close most days beats hitting a precise gram count on some days and missing badly on others.
Then make the number easy to hit. Split it across three to five meals using the table above, anchor each meal with one obvious protein source (eggs, chicken, fish, Greek yogurt, tofu, beans), and front-load breakfast: a 20-gram hole at 8 a.m. is annoying to fill at 10 p.m.
You do not have to weigh food forever, either. Track one normal eating day, see where your protein actually lands, and you will usually find the gap is one meal wide. Fix that meal, whether with a bigger portion at dinner or a scoop in the morning, and the rest of the plan mostly takes care of itself.
If you use a powder
PRIME Whey Protein
25g protein per serving, designed to help you hit your daily target. Isolate first blend, 30 servings, full label on the tub.
View PRIME →Protein decides what your body can build with; calories decide the direction. If you have not already, get your maintenance number from the TDEE calculator and pair the two targets in one plan. The tools hub lists every calculator we have shipped so far.
AT THE ANVIL
QUESTIONS, answered.
How much protein can the body use in one meal?
More than the old 30-gram rule says. Larger doses digest more slowly and keep feeding muscle for longer; nothing gets discarded. Splitting your total across three to five meals is still the practical move: steadier doses and easier appetite control. That's why the tool shows per-meal splits.
Do I need protein powder to hit these numbers?
No. Chicken, eggs, fish, dairy, tofu, and beans can cover any target on this page. Powder is a convenience: about 25 grams of protein per scoop with minimal cooking, useful when you're short on time or appetite. Hit the daily total first; where it comes from matters far less.
Should I use my current weight or my goal weight?
Current weight if you're reasonably lean already. If you carry a lot of extra body fat, current weight inflates the target, because protein needs track lean tissue more than total mass. Plug in a realistic goal weight instead and you'll get a number that is easier to eat and just as protective.
Is more protein always better for building muscle?
No. In the Morton meta-analysis, average gains flattened near 1.6 grams per kilogram per day, about 0.73 per pound, with the upper confidence bound around 1 gram per pound. Past that, extra protein mostly displaces the carbs and fat that fuel your training. Stay inside the band and spend your effort on consistency.