Free Tool
GLP-1 ProteinCalculator
Your daily protein band and calorie target, from the same deterministic engine that powers Metriq's coaching — built for weight loss that keeps the muscle.
On a GLP-1, appetite falls and protein quietly falls with it — and a steep deficit without enough protein is how weight loss becomes muscle loss. The GLP-1 protocol is the full answer; this calculator is the first number in it.
How the numbers are calculated
Resting energy comes from the Mifflin-St Jeor equation (Mifflin, St Jeor et al., American Journal of Clinical Nutrition, 1990 — the standard clinical estimate), scaled by a standard activity multiplier (1.2 sedentary through 1.9 athlete) to estimate your daily maintenance calories.
The calorie target applies a fat-loss deficit to that maintenance number: a gentle 10% if you're on a GLP-1 — the medication already restricts intake, so the risk worth engineering against is under-eating — or a standard 20% if you're not. No target is ever set below a 1,200 kcal safety floor, and it's shown as a ±5% range because precision theater helps nobody.
Protein is a band, not a point: 0.8–1.1 g per pound of body weight. There is no separate “GLP-1 protein formula” — the band is the same one Metriq prescribes without the medication, and we'd rather say that plainly than invent one. What changes on a GLP-1 is the calorie deficit above, and how hard the band is to reach on a suppressed appetite.
The full product goes further than this tool can: it folds in body-fat readings (which lower the protein basis when body fat is high), your actual food preferences and exclusions, wearable energy data, and weekly weigh-ins — and it adjusts the targets as your body changes. This page is the honest first pass, not the protocol.
Does being on a GLP-1 change how much protein I need?
No — the protein band is the same formula either way: 0.8 g per pound of body weight protects lean mass, 1.1 g optimises it. What the GLP-1 changes is everything around that number: appetite suppression makes the target harder to reach without planning, and the calculator uses a gentler 10% calorie deficit because the medication already restricts intake. Under-eating protein, not overeating, is the muscle-loss risk.
Why is protein shown as a range instead of one number?
A single large number is a daily pass/fail test, and most people fail it often enough to quit. The evidence for protecting lean mass in a deficit is solid from roughly 0.8 g per pound upward, and the returns above ~1.0 are small — so the floor is where the result is protected, the target is where it is optimised, and any day inside the band counted.
Is this medical advice?
No. These are nutrition estimates from your own inputs, not medical care, and not a substitute for it. Dosing, timing, and whether you're on a GLP-1 at all stay entirely between you and your prescriber — this tool never touches any of that.
Want the full picture on protecting muscle during GLP-1 weight loss? How to lose weight on GLP-1 medications without losing muscle — the long-form guide, with sources.
The fine print, in plain words
These numbers are estimates computed from your own inputs, in your browser — nothing you enter here is stored or sent anywhere. They are general nutrition guidance, not medical care, and not a substitute for it.
Metriq never touches your prescription — dosing, timing, and whether you're on a GLP-1 at all stay entirely between you and your prescriber. For a medical condition, prescription medication, or individualized clinical nutrition advice, that belongs with an appropriate healthcare professional.