Protein calculator
Enter your weight and goal. We return a daily protein target in grams, using the evidence-based grams-per-kilogram ranges. If you are losing weight, especially on a GLP-1, this is the number that decides whether the loss comes from fat or muscle.
How this calculator works
Protein need scales with body weight, and the target rises when you are in a calorie deficit. The calculator uses three evidence-anchored bands, in grams per kilogram of body weight.
- General health (0.8 to 1.0 g/kg). The RDA floor to avoid deficiency. Not a weight-loss target.
- Weight loss (1.2 to 1.6 g/kg). The range that preserves lean mass during a calorie deficit. The default for most people trying to lose fat.
- Preserve muscle (1.6 to 2.2 g/kg). The higher band for an aggressive deficit, heavy resistance training, or rapid GLP-1 weight loss.
Why this is the GLP-1 number
GLP-1 medications work fast, and rapid weight loss is where muscle is most at risk. In the STEP-1 trial of semaglutide, roughly a third of the weight lost was lean mass rather than fat. That is not a reason to avoid the medication; it is a reason to defend muscle while you take it. Two habits do most of the work: hit your protein target, and do some resistance training two or three times a week. Together they push more of the loss toward fat, which is the point.
If you are weighing a GLP-1, the first question is eligibility. The BMI-to-program calculator checks whether you meet the prescribing threshold and ranks the programs that serve your state.
Hitting the target on a smaller appetite
The catch on a GLP-1 is that you are eating less overall while needing more protein by proportion. Front-load it. Eat protein first at each meal, before fullness cuts the meal short, and aim for 25 to 40 grams per sitting across three or four meals. Whole food carries the load; a shake closes the gap on hard days.
Frequently asked questions
How much protein do I need to lose weight?
During a calorie deficit, most evidence points to 1.2 to 1.6 grams of protein per kilogram of body weight, well above the 0.8 g/kg RDA minimum. The extra protein preserves lean muscle while you lose fat and helps control hunger. For an aggressive deficit or heavy resistance training, the range runs up to about 2.2 g/kg.
Grams per kilogram or grams per pound?
Clinicians use grams per kilogram of body weight. Grams per pound is the same target in US units: 1.2 to 1.6 g/kg works out to roughly 0.55 to 0.73 grams per pound. This calculator shows both so you can use whichever is easier to track.
Why does protein matter more on a GLP-1?
Because GLP-1 weight loss is fast, and fast loss puts lean mass at risk. In the STEP-1 trial of semaglutide, roughly a third of the weight participants lost was lean mass, not fat. Hitting a protein target and doing some resistance training shifts more of the loss toward fat, which is the loss you actually want.
How do I hit a high protein target while eating less on a GLP-1?
Lead every meal with protein before appetite fades: eggs, Greek yogurt, chicken, fish, tofu, cottage cheese, legumes. Aim for 25 to 40 grams per meal across three or four meals. A protein shake is a practical way to close a gap on days when solid food is hard to finish.
Can you eat too much protein?
For healthy adults, intakes in these ranges are well tolerated. People with chronic kidney disease or specific medical conditions should set a target with their clinician rather than a calculator. This tool gives a general-population estimate, not medical advice.
Other calculators
- Calorie-deficit calculator: the daily target for each rate of loss.
- TDEE calculator: your full daily burn, resting plus activity.
- BMR calculator: your resting burn on its own.
- BMI-to-program calculator: your BMI and the programs you qualify for.
