Mounjaro Weight Loss Calculator
See how your weight has changed while taking Mounjaro. Enter your starting and current weights for pounds or kilograms lost, percentage change, and optional weekly and goal progress.
- 1Enter two weights
- 2Add weeks or a goal
- 3See your recorded change
A QUICK WALKTHROUGH
How the Mounjaro Weight Loss Calculator works
This tool uses only the measurements you enter. It does not apply a trial average to your body or forecast a result.
Choose pounds or kilograms
Use the same unit for your starting, current and optional goal weights.
Enter two measured weights
The calculator subtracts your current weight from your starting weight and reports the percentage change.
Add elapsed weeks if you know them
The total change divided by weeks gives your past average per week. It does not project future weeks.
Add an optional goal
See the remaining difference and the share of your starting-to-goal distance already covered. Discuss the goal with your clinician.
What Mounjaro studies report about weight change
For context, Table 5 of the U.S. Mounjaro prescribing information reports weight changes at week 40 in SURPASS-2. The adults in that trial had type 2 diabetes, were taking metformin, and were assigned to different Mounjaro groups. These figures are group averages from that setting. They are not inputs to the calculator above and should not be used to forecast your weight.
| Trial group | Average change at week 40 |
|---|---|
| Mounjaro 5 mg | 7.6 kg loss (about 16.8 lb) |
| Mounjaro 10 mg | 9.3 kg loss (about 20.5 lb) |
| Mounjaro 15 mg | 11.2 kg loss (about 24.7 lb) |
The 2.5 mg starting strength and the 7.5 mg and 12.5 mg strengths do not have equivalent week-40 SURPASS-2 study arms in this table. We do not invent values for them. Trial-group differences are not dose advice.
How to calculate Mounjaro weight loss percentage
Weight change = starting weight − current weight. A positive answer means weight decreased; a negative answer means it increased. Percentage change = weight change ÷ starting weight × 100. For example, a measured change from 200 lb to 185 lb is 15 lb, or 7.5% of the starting weight. This is your entered measurement difference, not an estimate of medication effect.
If you enter elapsed weeks, the tool divides that change by the number of weeks. A 15 lb change over 12 weeks averages 1.25 lb per week across the full interval. It does not mean every week changed by that amount. With an optional goal, remaining distance equals current weight minus goal weight, never less than zero, and progress equals change divided by starting-to-goal distance. The goal math is informational and does not recommend a target or rate.
Mounjaro and weight management are different questions
In the United States, Mounjaro is indicated for type 2 diabetes, while Zepbound is the tirzepatide brand used for weight-management indications. Weight change appeared in Mounjaro diabetes trials, but those results cannot predict an individual's response. Your measured trend can also be influenced by many factors outside this calculator. Speak with your healthcare professional about unexpected changes or treatment decisions.
Mounjaro Weight Loss Calculator FAQs
How do I calculate weight loss while taking Mounjaro?
Subtract your current weight from your starting weight. Divide the difference by your starting weight and multiply by 100 to get a percentage. This calculator does both using your recorded weights. It does not estimate how Mounjaro will work for you.
How much weight did people lose on Mounjaro in the 40-week trial?
In SURPASS-2, adults with type 2 diabetes taking metformin had average weight changes at week 40 of 7.6 kg with Mounjaro 5 mg, 9.3 kg with 10 mg, and 11.2 kg with 15 mg. These were group averages from a specific trial, not personal predictions.
What was the average weight loss with Mounjaro 5 mg?
The Mounjaro U.S. prescribing information reports an average 7.6 kg (about 16.8 lb) decrease at week 40 for the 5 mg SURPASS-2 group. People in the study had type 2 diabetes and were taking metformin. Your result may differ.
What was the average weight loss with Mounjaro 10 mg?
The 10 mg group in SURPASS-2 had an average 9.3 kg (about 20.5 lb) weight decrease at week 40. That trial average cannot tell an individual what to expect or which dose to use.
What was the average weight loss with Mounjaro 15 mg?
The 15 mg group in SURPASS-2 had an average 11.2 kg (about 24.7 lb) weight decrease at week 40. It is a group result for adults with type 2 diabetes on metformin, not a guarantee.
Can I predict Mounjaro weight loss after one month or six months?
No reliable personal forecast follows from the week-40 SURPASS-2 averages. This calculator measures change between two weights you enter. If you provide elapsed weeks, it reports your past average per week, not future weight loss.
How do I calculate my weekly weight change?
Subtract current weight from starting weight, then divide by elapsed weeks. For example, a 12 lb decrease over 12 weeks averages 1 lb per week. Actual week-to-week changes can vary.
Is Mounjaro approved for weight loss in the United States?
Mounjaro is a tirzepatide medicine approved in the United States for type 2 diabetes indications, not as a weight-loss medicine. Zepbound is the tirzepatide brand with a weight-management indication. Ask your clinician about the medicine prescribed for you.
Can GLP Buddy track my Mounjaro weight trend?
Yes. GLP Buddy can record Mounjaro injections and weight entries so you can review your own trend over time. The app does not replace clinical care.
Sources
Source checked . This page is educational and does not provide medical advice. Mounjaro is an Eli Lilly trademark. GLP Buddy is not affiliated with Eli Lilly.