Protein calculator for weight loss
An honest protein target for a calorie deficit — built to protect muscle, not to sell you a shortcut.
We want to be upfront about what this calculator does and doesn't claim. Protein isn't a metabolism-boosting trick, and we're not going to tell you a gram target will melt fat off on its own. What a large body of exercise-nutrition research does show is narrower and more actionable: when you eat fewer calories than you burn, your body pulls energy from both fat and muscle unless you give it a reason not to. Adequate — and for some people, higher — protein intake is one of the best-supported reasons. It's the difference between losing weight and losing the muscle you'll want to have once the diet is over.
This matters especially if you're 50 or older, since a calorie deficit compounds the age-related muscle loss (sarcopenia) that's already working against you. The same math this calculator uses everywhere else on CountProtein applies here too — there's no separate "weight loss mode," because the activity-based range already accounts for it. The International Society of Sports Nutrition's position stand specifically notes that resistance-trained individuals in a calorie deficit may benefit from protein intakes toward the higher end of the evidence-based range, which is why the "very active" and "lift weights 2+ times a week" options below push your target up rather than down.
Answer the five questions honestly — based on your current weight and activity, not a future goal — and you'll get a daily and per-meal target, plus what that looks like in everyday food, so you can plan meals that keep you full and keep your muscle intact while the scale moves.
Calculator
Questions about protein and weight loss
Does eating more protein help me lose weight?
Protein itself doesn't have a special fat-burning effect, and we won't claim otherwise. What the research does support is more specific and, honestly, more useful: when you're eating fewer calories than you burn, higher protein intake helps you hold onto muscle instead of losing it along with fat. That's the claim this calculator is built to support — not weight loss itself.
Why doesn't this calculator have a separate 'cutting' formula?
Because the same evidence-based, activity-adjusted range already covers a calorie deficit. The International Society of Sports Nutrition's position stand notes that people in a hypocaloric (deficit) period who are resistance-trained may benefit from protein intakes toward the higher end of the range to protect lean mass. Rather than bolt on a separate untested formula, we point you to the "very active" or "lift weights 2+ times a week" activity options, which already land you in that higher range.
Should I increase my activity level answer if I plan to work out more while losing weight?
Answer based on your actual current activity, not your goal — the calculator recalculates instantly, so you can select "very active" or the resistance option once your training picks up and watch your target adjust. If you're planning to start resistance training specifically to protect muscle during a cut, that's exactly the scenario the research on the higher end of the range addresses.
Will a higher protein target make it harder to stay in a calorie deficit?
That depends on your total calorie target, which this calculator doesn't set — it only tells you the protein piece. Many people find higher-protein meals more filling per calorie, which can make a deficit easier to sustain, but that's a side effect we're not going to oversell here; it isn't the core, well-supported claim this tool is built on.
Track your target automatically
CountProtein turns this number into a daily habit — snap a photo of your meal and see your grams, without having to count every calorie too.
Track it with the appRead more: Protein basics · Full calculator + methodology