Retatrutide Weight Loss Calculator
Retatrutide weight loss calculator: see what the average results from the Phase 2 and Phase 3 trials would mean at your starting weight, in pounds or kilograms.
What the trial average would mean at your start weight
Based on the 12 mg, 68 weeks (TRIUMPH-4) average of 28.7%. A trial average, not a prediction for any one person. Results vary with dose, adherence and starting weight.
How the projection works
The calculator multiplies your starting weight by the average percentage lost in the trial you pick. At 220 lb, the TRIUMPH-1 average of 28.3% works out to about 62 lb, ending near 158 lb.
The trial numbers behind it
| Trial | Dose | Time on treatment | Average weight lost |
|---|---|---|---|
| Phase 2 (338 adults) | 4 mg | 48 weeks | 17.1% |
| Phase 2 | 8 mg | 48 weeks | 22.8% |
| Phase 2 | 12 mg | 48 weeks | 24.2% |
| Phase 3, TRIUMPH-1 | 12 mg | 80 weeks | 28.3% |
| Phase 3, TRIUMPH-4 | 12 mg | 68 weeks | 28.7% |
TRIUMPH-4 enrolled adults with obesity and knee osteoarthritis, so its population differs from the other trials.
What an average does not tell you
Averages hide a spread. Some people in every group lost far more than the average and some far less. Starting weight, how long someone stays on treatment, the dose they reach and how well they tolerate it all move the result.
Before you plan around a number
Weight loss on retatrutide in the trials came with regular clinic visits, dose steps and lifestyle advice. If you are weighing retatrutide for sale online, know that no approved version exists yet, so none of that support comes in the box.
Frequently asked questions
How much weight could I lose on retatrutide?
Nobody can predict one person's result. In the Phase 2 trial, the 12 mg group lost an average of 24.2% of body weight after 48 weeks. In the Phase 3 TRIUMPH-1 trial, the 12 mg group lost an average of 28.3% over 80 weeks. Individual results in both trials ranged widely around those averages.
Why does the calculator use percentages?
The trials report weight loss as a percentage of starting weight, so the fairest way to translate them is to apply the same percentage to your weight.
Do lower doses lose less weight?
In the Phase 2 trial, yes. Average loss at 48 weeks was 8.7% on 1 mg, 17.1% on 4 mg, 22.8% on 8 mg and 24.2% on 12 mg, compared with 2.1% on placebo.
Is the placebo group included?
The calculator shows retatrutide group averages. The Phase 2 placebo group lost an average of 2.1% over 48 weeks with the same diet and activity advice.
Sources
- Triple-Hormone-Receptor Agonist Retatrutide for Obesity: A Phase 2 Trial (Jastreboff AM et al.). New England Journal of Medicine, 2023. nejm.org
- TRIUMPH-1 topline results: retatrutide 12 mg lost an average of 70.3 lbs (28.3%) over 80 weeks. Eli Lilly and Company via PR Newswire, 2026. prnewswire.com
- TRIUMPH-4 topline results: retatrutide 12 mg lost up to an average of 28.7% at 68 weeks. Eli Lilly and Company via PR Newswire, 2025. prnewswire.com