Tirzepatide Weight Loss Calculator
See a personalized, month-by-month estimate of tirzepatide weight loss (Mounjaro or Zepbound), based on the average outcomes reported in the SURMOUNT-1 clinical trial.
Medical Disclaimer
This calculator is for educational and informational purposes only and does not provide medical advice, diagnose any condition, recommend or prescribe treatment, or guarantee results. Estimates are based on information you provide and published clinical-trial averages. Individual results can vary significantly.
Estimates are based on average outcomes reported in the STEP 1 (semaglutide) and SURMOUNT-1 (tirzepatide) clinical trials. Individual results can vary significantly and are influenced by factors such as dosage, diet, and adherence.
Do not start, stop, or change any medication based on the results of this calculator. Always consult a qualified healthcare professional regarding medications, treatment options, risks, side effects, and your individual health needs.
The data behind this estimate
Tirzepatide is the active ingredient in Mounjaro and Zepbound. In the SURMOUNT-1 trial, adults taking tirzepatide at the highest studied dose (15 mg weekly) lost an average of about 20.9% of their starting body weight over 72 weeks. This calculator applies that published average, and the trial's approach-to-plateau pattern, to your own starting and goal weight.
- Trial: SURMOUNT-1 (tirzepatide 15 mg weekly, highest dose)
- Duration: 72 weeks
- Average total body-weight reduction: ~20.9%
Want the semaglutide numbers too? Try the semaglutide calculator or read the full semaglutide vs. tirzepatide comparison.