Protein intake calculator: grams a day, and per meal

How much protein you need for lifting comes down to one number, your bodyweight, and one range. Enter your bodyweight below for the range in grams a day and the same amount split across three or four meals.

Work out your daily protein

The calculator needs JavaScript, which looks to be switched off. The numbers here are the worked example, and the formula below works by hand.

How the calculator works

It multiplies your bodyweight by the two ends of the range and divides by the number of meals:

• In pounds: bodyweight × 0.7 and bodyweight × 1, in grams a day. At 180 lb: 126 to 180 g.
• In kilograms: bodyweight × 1.6 and bodyweight × 2.2. At 82 kg: about 131 to 180 g.
• Per meal: the daily range divided by three or four. At 180 lb: 42 to 60 g over three meals, 32 to 45 g over four.

The pound and kilogram ranges are rounded versions of each other, so the same person gets a few grams more at the low end in kilograms. Either is fine. The range is wide on purpose: anywhere in it is a reasonable daily target.

Where the range comes from

The low end is where the gains stopped growing. A 2018 meta-analysis of 49 trials of protein supplementation and lifting, with 1,863 healthy adults training for at least six weeks, estimated that total protein beyond about 1.6 g per kg of bodyweight a day brought no further gains in lean mass.¹ That figure has a margin of error, and its upper end, 2.2 g per kg, is the top of the range: the authors suggest about 2.2 g per kg "may be prudent" for people trying to get the most from their training.¹

The International Society of Sports Nutrition's position stand puts the range a little lower, at 1.4 to 2.0 g per kg a day for most people who exercise, to build or keep muscle.² The two overlap across most of the range. In pounds, 1.6 to 2.2 g per kg rounds to 0.7 to 1 g per lb, the version on calories and protein.

Spreading it across the day

The same position stand gives an amount per serving, about 0.25 g of protein per kg of bodyweight or 20 to 40 grams, ideally spread evenly every three to four hours.² A 2015 review of higher-protein diets suggested meals of at least about 25 to 30 grams.³ That's why the calculator splits the day into three or four meals, and why roughly 30 to 40 grams a meal is the practical version for most people who lift; if your three-meal split comes out higher, a fourth meal or a snack spreads it out.

Build each meal around a protein source, and if you're short at the end of the day, a shake or a yogurt closes the gap. Calories and protein has the food list and the calorie side of the picture; the 80/20 approach covers eating it without strict rules.

What it doesn't do

It gives a protein range and nothing else: no calories, no weight-loss target and no goal weight. Calories are a separate number, and calories and protein explains how to estimate yours.

It's general guidance for healthy adults who lift. If you have kidney disease or follow a medical diet, your doctor leads on protein, not this page; I'm a fitness coach, not a doctor or registered dietitian.

Questions

How much protein do I need to build muscle?

The same range: 0.7 to 1 g per pound a day, 1.6 to 2.2 g per kg, alongside lifting. In the 2018 meta-analysis, the extra gains in lean mass leveled off at about 1.6 g per kg, and the authors suggest about 2.2 for people trying to get the most from training.¹ Protein supports the training; it doesn't replace it. Progressive overload is the training side.

Is the protein range different for women?

The range is per pound or per kilogram of bodyweight, so the calculator works the same for everyone. The 2018 meta-analysis included 14 groups of women only and saw no clear difference between the sexes, though the authors note the data are limited and far less work has been done in women than in men.¹ Strength training for women covers the training side.

Do I have to hit an exact number?

No. Anywhere in the range counts, and landing close most days is the win. Pick a number inside it you can reach without forcing it.

If you'd rather not work it out alone

A number is the easy part; landing near it on workdays, weekends and nights out is the habit. In coaching, you learn to use calories and protein to support your goals without overcomplicating food. Coaching to build muscle explains how that works, and apply tells me where you're starting.