Calculator
Retatrutide cost calculator
Short answer
Cost = vials × price, where vials = ceil(total mg ÷ vial mg). Example: 8 mg weekly for 4 weeks is 32 mg; 10 mg vials at $100 means 3.2 vials, so 4 vials and $400 ($320 if the partial vial carries over), or $10 per mg. You enter the price; as of Oct 19, 2026.
- Cost, whole vials
- $900.00
- Vials needed
- 9 (8.4 exact)
- Total amount
- 84 mg
- Cost if partial vial carries over
- $840.00
- Average per 4 weeks
- $210.00
- Per mg
- $10.00
| Weeks | mg per week | mg in block |
|---|---|---|
| 1–4 | 2 | 8 |
| 5–8 | 4 | 16 |
| 9–12 | 6 | 24 |
| 13–16 | 9 | 36 |
84 mg ÷ 10 mg per vial = 8.4 vials → 9 whole vials × $100 = $900.00.
Math, parameters and sources: model card.
How the cost math works
The calculator adds up every weekly amount in the period, divides by the vial size and rounds up to whole vials. It also reports the fractional number of vials, which is the fairer average when a partly used vial carries into the next period. Cost per mg is the price divided by the vial size. Retatrutide has no lawful retail price; it is investigational and available only in clinical trials.
Products sold online as "research" retatrutide are unapproved new drugs according to FDA warning letters (FDA, Aug 24, 2026), and Lilly has said the compound is not available outside its trials (Eli Lilly, Aug 12, 2026).
Frequently asked questions
How much does retatrutide cost per month?
- There is no legal retail price: retatrutide is investigational and not sold as an approved product. Products sold online as "research" retatrutide are unapproved, and the FDA has issued warning letters to sellers. This calculator only does arithmetic on a price you enter.
How many mg is the Phase 3 retatrutide ladder over 16 weeks?
- The published 12 mg arm steps 2, 4, 6 and 9 mg, four weeks each, before 12 mg. Over those first 16 weeks that totals 4 × (2 + 4 + 6 + 9) = 84 mg. The calculator adds up any ladder the same way.
Why are whole vials and fractional vials different?
- Whole vials are what you would need to have on hand for the period (rounded up). The fractional figure assumes the partial vial carries into the next period, which gives the true average cost per period.
Does the calculator include vendor prices?
- No. Prices are your input only. GLP Ladder lists no sellers and prefills no prices, so the result is only as good as the number you type.
Is retatrutide FDA approved?
- No. As of Oct 19, 2026 retatrutide is investigational. Lilly reported Phase 3 results in 2026 and said it plans to submit to the FDA in the first quarter of 2027. It is legally available only to participants in Lilly clinical trials.
Sources
- Lilly's triple agonist, retatrutide, delivered powerful weight loss in pivotal Phase 3 obesity trial. Eli Lilly and Company (via PR Newswire; also investor.lilly.com), May 21, 2026. Accessed Oct 19, 2026.
- Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity. N Engl J Med (abstract via PubMed PMID 42814954; doi:10.1056/NEJMoa2604169), Sep 29, 2026. Accessed Oct 19, 2026.
- LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist in people with type 2 diabetes: a phase 1b, multicentre, double-blind, placebo-controlled, randomised, multiple-ascending dose trial. The Lancet 2022;400(10366):1869-1881 (abstract via PubMed PMID 36354040; doi:10.1016/S0140-6736(22)02033-5), Oct 27, 2022. Accessed Oct 19, 2026.
- Study Protocol J1I-MC-GZBF(b) for NCT04881760 (Prot_000.pdf). Eli Lilly and Company, hosted on ClinicalTrials.gov, Aug 29, 2022. Accessed Oct 19, 2026.
- Warning Letter: Peak Performance Peptides, MARCS-CMS 735127. U.S. Food and Drug Administration, Aug 24, 2026. Accessed Oct 19, 2026.
- Lilly calls on online platforms, payment companies and regulators to shut down the illegal retatrutide black market. Eli Lilly and Company (via PR Newswire), Aug 12, 2026. Accessed Oct 19, 2026.
Printed from GLP Ladder. To recreate this result, open https://glpladder.com/tools/retatrutide-cost/
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