What BMI Do You Need for Mounjaro or Wegovy?

BMI — body mass index — is a widely used screening measure calculated from height and weight. It gives prescribers a quick reference point when assessing whether a weight-management medicine may be appropriate, though it is never the only factor considered.

Common BMI criteria

Based on prescribing guidelines used in a number of countries, the general thresholds most commonly referenced are:

• BMI 30 or above — typically the standard qualifying threshold for medicines like Mounjaro and Wegovy
• BMI 27 or above — may apply where the person also has at least one weight-related condition, such as type 2 diabetes, high blood pressure, or high cholesterol

These figures align with criteria outlined in the electronic Medicines Compendium (eMC) product information for both tirzepatide and semaglutide. Your prescriber will assess whether these criteria apply to your individual situation.

What the minimum BMI actually means

There is no single universal minimum BMI for Mounjaro or Wegovy that applies in every country or every clinical setting. The thresholds above represent what is commonly used, but eligibility also depends on factors such as existing health conditions, other medications, and local prescribing guidance. Whether you were prescribed through a national health programme or privately, your prescriber will have made that assessment based on your personal history.

BMI is a starting point, not the whole picture

BMI has well-known limitations — it does not account for muscle mass, body composition, or where weight is carried. Many prescribers use it alongside waist measurements, metabolic markers, and other clinical factors. If you have questions about why you were — or were not — prescribed these medicines, your prescriber or doctor is the right person to ask.

For more detail on how BMI thresholds relate to eligibility assessments, see our pages on what BMI qualifies for Mounjaro and the BMI needed for Mounjaro prescriptions.

Once you are already prescribed and taking Mounjaro or Wegovy, keeping a clear record of your weight and body measurements over time becomes one of the most valuable things you can do. GLP Trackr's weight and body tracking feature lets you log your weight regularly and watch your trend line develop — so you can see genuine progress even when day-to-day fluctuations make the scale feel noisy.

The app's daily check-in takes around 30 seconds each morning and builds up a week-by-week picture of how your body is changing. Over time, the insights tool can surface patterns you might not notice otherwise — such as how your food intake, sleep, or step count relates to your results. You can also generate a doctor report to bring a clear summary of your journey to your next prescriber appointment.

For broader tracking tools, including calorie and protein targets that work alongside your weight data, visit our GLP Trackr calorie calculator hub. You may also find our overview of BMI and Mounjaro useful as a companion read.

GLP Trackr is a tracking and journaling companion — it is not a prescribing service and does not provide medical advice. Any questions about your eligibility, dose, or suitability should be directed to your prescriber or doctor, who knows your full history.

Start logging your weight, measurements, and weekly progress today — GLP Trackr is free to try for 7 days on the App Store and Google Play.