Weight-loss projection calculator
See an estimated week-by-week curve based on clinical-trial averages. Adjust your starting weight, drug, and timeframe.
This tool estimates total body-weight loss over time using the average results from each drug's pivotal clinical trial. Real results vary widely from person to person and depend on dose, diet, activity, and how long you stay on treatment. Use this as a rough planning guide, not a promise.
Model uses an ease-out curve approaching each drug's trial-average loss at its study endpoint.
Projected curve
Week-by-week estimate
| Week | Projected weight | Total lost | % of body weight |
|---|
About these numbers
The percentages reflect average total body-weight reductions reported in the medications' pivotal trials: roughly 15% for semaglutide 2.4 mg (Wegovy) at 68 weeks and roughly 20% for tirzepatide (Zepbound) at 72 weeks. Weight loss generally builds gradually during dose titration and then continues more slowly. Stopping treatment often leads to partial regain.
Your results depend on many personal factors. Discuss realistic goals with your prescriber.
Sources: FDA.gov drug labeling for Wegovy and Zepbound; published pivotal trial summaries.
Why the curve isn't a straight line
If weight loss were steady, you could just divide the total by the number of weeks. It doesn't work that way. In the real trials, most people started on a low "titration" dose that ramps up over the first weeks to reduce side effects, so early loss is modest. As the dose reaches its target, loss accelerates, and later it flattens as the body settles toward a new equilibrium. This projection mirrors that shape with an ease-out curve that approaches each drug's trial-average endpoint — which is why the weekly numbers in the table start small, build in the middle, and taper near the end.
Two practical takeaways follow from that shape. First, don't judge the medication by the first month; the steepest progress usually comes after you reach the full dose. Second, the endpoint in these trials was 68–72 weeks, so the biggest results assume more than a year of continuous treatment — which is exactly why affordable, sustained coverage matters.
How coverage affects your results
Because the largest weight changes show up only after a year or more, staying on treatment is what turns a trial average into a personal result — and cost is the most common reason people stop early. That's where the Bridge program comes in: by capping an approved GLP-1 at a flat $50 monthly copay through the end of 2027, it removes the sticker price that pushes many people to quit before the curve pays off. If the projection above looks worth pursuing, the next steps are confirming you qualify and understanding the real monthly cost under each coverage scenario.
Frequently asked questions
How much weight will I actually lose?
The projection uses trial averages — about 15% of body weight on Wegovy over 68 weeks and about 20% on Zepbound over 72 weeks — but your own result depends on dose, diet, activity, other health conditions, and how long you stay on treatment. Treat the numbers as a planning range, not a guarantee.
Why does the early progress look slow?
Most people begin on a low dose that increases gradually to limit side effects, so the first weeks show less change. Loss typically speeds up once you reach the target dose, then tapers as you approach a new set point — the pattern this tool models.
What happens if I stop taking it?
Research shows partial weight regain is common after stopping a GLP-1, because its appetite-regulating effect ends. Any decision to pause or stop should be made with your prescriber, who can weigh the trade-offs for your situation.