Ozempic tells you when to stop.
Math tells you what to eat.
Studies show 25–40% of the weight dropped on a GLP-1 is lean tissue — not fat. We raise your protein target, set a calorie floor, and tell you exactly how much muscle you're at risk of losing if you go too fast. Drag the numbers below.
Here's what he told the calculator.
In about two minutes, this is exactly what you'll fill in for yourself.
That's the whole input. No logging. No fasting schedule. Just who you are today and where you want to be.
The scale drops beautifully. The mirror tells a harder story.
When appetite disappears, so does most of what keeps your muscle fed. The weight you're dropping includes water, glycogen, and a significant share of lean tissue. The Math Diet isn't an alternative to GLP-1 — it's the other half of the problem the drug doesn't solve.
- A protein target you can hit without being hungry.2.2 g/kg of lean body mass, spread across 3–4 meals. The number the body needs, whether you're craving it or not.
- A floor on calories.Below 1,200 (women) or 1,500 (men), the body downregulates everything it can — including the things you wanted to keep.
- A muscle-loss warning the drug won't give you.Losing over 1% body weight per week, we flag it. The scale is misleading you — and we tell you how much.
The scale moves faster than your fat does.
If you've dropped 5 kg in a week before, you know the feeling. Real — but not fat. Here's what actually comes off, and in what order.
The one you want gone. 9 Cal per gram. Can't be lost faster than the math allows — about 0.5–1 kg per week at a sane deficit.
Carbs are stored with 2 g of water per gram of carb. Drop carbs, drop the water with them. Comes off in days. Goes back on in a meal.
The one you don't want gone. Lost when protein is too low or deficit is too steep. Especially at risk on GLP-1s, where appetite makes hitting protein hard.
Excess water the body holds while processing junk food. Clean up the diet, inflammation drops. Not fat, but genuinely makes you look leaner.
This is why fast-loss diets look miraculous for a week, then stall. You flushed water and glycogen — cheap to lose, cheap to put back on. Fat is the expensive one at 9,000 Cal a kilo, and the only one that actually changes how you look. The calculator above is calibrated to the expensive one.
Four steps. Three minutes. Zero fluff.
Age, height, weight. Two taps pick your activity level. Fifteen seconds.
How many kilos off. By when. No vague "feel better" targets. A number, a date.
BMR. Maintenance. Diet calories. Macros. Refeed. Eight lines. Everything.
Track in any app. MyFitnessPal, Cronometer, napkin. The number does the rest.
$7. Once. Forever.
Your numbers change as your weight does. Lifetime access means you come back, recalculate, and carry on — no resubscribing, no upsells, no funnel. One price, done.