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Mounjaro Weight Loss Calculator
This calculator looks up the average weight change published for Mounjaro (tirzepatide) in SURPASS-2. It reports what happened in a trial. It does not predict what will happen to you.
These figures come from a trial in adults with type 2 diabetes, where weight loss is typically smaller. For the obesity-trial results of the same medication (tirzepatide), see the Zepbound weight loss calculator.
The published result
In SURPASS-2, adults with type 2 diabetes taking Mounjaro 10 mg had lost an average of 9.3 kg (20.5 lb) by week 40, from an average starting weight of 94.8 kg. This trial was in people with type 2 diabetes, where weight loss is typically smaller than in obesity trials of the same medication; see the Zepbound page for those.
This is the average result of a clinical trial, not a prediction of yours.
The dose is the maintenance dose each group was assigned to.
Other medications: Zepbound weight loss calculator · Ozempic weight loss calculator · Wegovy weight loss calculator
What the trial found, by dose
| Semaglutide 1 mg once weekly (n=468) | 5 mg once weekly (n=470) | 10 mg once weekly (n=469) | 15 mg once weekly (n=469) | |
|---|---|---|---|---|
| Average starting weight | 93.7 kg | 92.5 kg | 94.8 kg | 93.8 kg |
| Average change at week 40 | −5.7 kg | −7.6 kg | −9.3 kg | −11.2 kg |
SURPASS-2 (ClinicalTrials.gov NCT03987919) enrolled 1,879 adults with type 2 diabetes inadequately controlled on metformin alone and ran for 40 weeks. It compared Mounjaro with semaglutide 1 mg once weekly (active comparator; this trial had no placebo arm). How the figures were analysed: Modified intent-to-treat population (randomized and exposed to at least one dose). Least-squares mean from ANCOVA (label Table 5, footnotes a and b).
Source: MOUNJARO (tirzepatide) injection prescribing information, Section 14, Table 5. U.S. National Library of Medicine, DailyMed. Label effective August 27, 2026; opened September 18, 2026. Read the prescribing information on DailyMed · SURPASS-2 on ClinicalTrials.gov
How this calculator works
It looks up the average change in body weight, in kilograms, that the Mounjaro prescribing information prints for the dose you choose, and shows it next to that group's average starting weight. It does not scale the figure to your weight, because the label reports kilograms for a group, not a percentage.
There is no week-by-week view. The prescribing information prints the result at the end of the trial only, so the calculator shows that result and does not estimate the weeks in between or anything after the trial ended.
Mounjaro weight loss calculator questions
How much weight do people lose on Mounjaro?
In SURPASS-2, the average weight loss at week 40 was 7.6 kg on 5 mg, 9.3 kg on 10 mg and 11.2 kg on 15 mg, against 5.7 kg on semaglutide 1 mg once weekly. These are trial averages; individual results varied widely.
Is this a prediction of my weight loss on Mounjaro?
No. It is a lookup of the average result published for a clinical trial. It cannot account for your health, your dose changes, your diet or your activity, and individual results in the trial varied widely. Talk to your prescriber about what to expect.
How long did the Mounjaro trial last?
SURPASS-2 ran for 40 weeks. No result past the final week is shown, because the trial ended there.
Who took part in SURPASS-2?
SURPASS-2 enrolled 1,879 adults with type 2 diabetes inadequately controlled on metformin alone.
Why are the Mounjaro results in kilograms rather than percent?
Because that is how the Mounjaro prescribing information reports body weight for this trial. The figure is shown as printed, next to the group's average starting weight, rather than converted into a percentage the label does not state or scaled to your own weight.
Why is the weight loss here smaller than on the Zepbound page?
The trials are different and cannot be compared directly. SURPASS-2 enrolled adults with type 2 diabetes inadequately controlled on metformin alone and ran 40 weeks. SURMOUNT-1, shown on the Zepbound page, enrolled adults with obesity (BMI ≥30), or overweight (BMI 27 to <30) with at least one weight-related condition; type 2 diabetes excluded and ran 72 weeks.
Where do these numbers come from?
MOUNJARO (tirzepatide) injection prescribing information, Section 14, Table 5. U.S. National Library of Medicine, DailyMed (label effective August 27, 2026; SURPASS-2, ClinicalTrials.gov NCT03987919). Every figure on this page is copied from that document.
Can this calculator tell me what Mounjaro dose to take?
No. It does not recommend, set or adjust a dose. Your dose and how quickly it is increased are decided by your prescriber, following the prescribing information.
By GLP AI / Editorial. The trial figures and result wording on this page were reviewed by Teresa Maze, RDN, on September 18, 2026. The review did not cover anything else on the page.
Medical Disclaimer
This article is for informational purposes only and does not constitute medical advice. The information provided should not be used for diagnosing or treating a health condition. Always consult your healthcare provider before starting, stopping, or changing any medication or treatment plan. Individual results may vary.