Protein Calculator for Weight Loss — 1.2 to 1.6 g/kg

Cutting calories without holding protein up means losing muscle alongside fat. The target during weight loss is 1.2 to 1.6 g of protein per kilogram of body weight, in meals of at least 25 to 30 g — and that range is no longer a diet-specific prescription. It is what the current Dietary Guidelines ask of everyone. The calculator uses the top of it; enter your weight in kilograms.

The range, and the two documents behind it

A 2015 review in the American Journal of Clinical Nutrition pulled together the trials on protein and body weight management and landed on “higher-protein diets that contain between 1.2 and 1.6 g protein · kg⁻¹ · d⁻¹” with “meal-specific protein quantities of at least ∼25-30 g protein/meal.”

Eleven years later the Dietary Guidelines for Americans, 2025–2030 set a general population goal of “1.2–1.6 grams of protein per kilogram of body weight per day.” Identical numbers. What the 2015 review called a higher-protein diet is what federal guidance now calls a normal one, which reframes this page: you are not adopting a special regimen to lose weight. You are holding the ordinary target while the calories around it come down.

Compared with lower-protein diets at the same calorie deficit, those trials showed greater weight loss, greater fat mass loss, and preservation of lean mass. Same deficit, better composition of what came off.

The joint sports nutrition position paper from Dietitians of Canada, the Academy of Nutrition and Dietetics and ACSM reaches the same conclusion from the athletic side: when energy availability is reduced to cut body weight or fat, “higher protein intakes are needed to support MPS” — muscle protein synthesis — “and retention of fat-free mass,” with intakes as high as 2.0 g/kg cited for that situation.

From the scale to the target

Convert before you multiply: pounds ÷ 2.205 = kilograms.

Body weight	In kilograms	1.2 g/kg	1.6 g/kg
140 lb	63.5 kg	76 g	102 g
160 lb	72.6 kg	87 g	116 g
180 lb	81.6 kg	98 g	131 g
200 lb	90.7 kg	109 g	145 g
220 lb	99.8 kg	120 g	160 g
250 lb	113.4 kg	136 g	181 g

One judgment call the table cannot make for you: at a high body fat percentage, calculating on current weight inflates the target, because fat mass has no protein requirement. Some dietitians calculate on a goal weight or on lean body mass instead. If your number looks unreachable, that is usually why, and it is a good reason to ask a professional rather than to give up on the target.

What protein does, stated honestly

It is easy to oversell this. The same review that recommends the range is careful about the mechanism, and so is worth quoting against the marketing.

Satiety: a modest effect. Higher-protein meals produce more perceived fullness and higher satiety hormones — but the evidence does not support people eating less at the next meal as a result.

Lean mass: this is the real win. In a deficit the body will draw on muscle as well as fat, and higher protein plus resistance training is what keeps the loss weighted toward fat.

Adherence: the review’s own emphasis. Improvements showed up in people who actually followed the higher-protein regimen. A 120 g target you hit six days a week beats a 180 g target you abandon.

Spreading it out

Twenty-five to thirty grams per meal is the operative number, and breakfast is where American diets usually fall short. Three meals at 30 g plus one snack at 20 g gets a 110 g day done without any single meal being unusual.

If the deficit itself is what you are still figuring out, the target on this page sits on top of it rather than replacing it. For the opposite goal, see the protein calculator for muscle gain; for the underlying arithmetic and every other life stage, the protein calculator.

This content is informational and does not replace evaluation by a physician or a registered dietitian.