Retatrutide Reconstitution & Dose Calculator
Retatrutide is an investigational triple agonist (it acts on the GLP-1, GIP, and glucagon receptors) from Eli Lilly. As of now it is still in clinical trials and is not FDA-approved. This free calculator turns a Retatrutide vial plus bacteriostatic water into the exact insulin syringe units to draw. It is unit-conversion math, not a dosing recommendation. Retatrutide vials are commonly 10 mg, 15 mg, 20 mg, so the tool below starts at 10 mg; change any field to match your own vial.
Reconstitution calculator
Pick your peptide, vial size, and BAC water. Get exact units to draw on a 1 mL insulin syringe.
Pick your peptide
Type to search, or pick from the dropdown. Auto-fills the recommended vial size.
- • Standard insulin syringe = 100 units total
- • Small markings = 1 unit each
- • Large markings = 10 units (0.1 mL)
- • 100 units = 1 mL
Always verify reconstitution math against a second source before any dose you actually inject.
Retatrutide concentration at a glance
Concentration is just vial mg divided by the bacteriostatic water you add. A more dilute mix gives a bigger, easier-to-read draw on the syringe. Here is a 10 mg Retatrutide vial at three common water volumes (U-100 insulin syringe, where 1 unit = 0.01 mL):
| BAC water | Concentration | Per insulin unit | 50 units draws |
|---|---|---|---|
| 1 mL | 10 mg/mL | 100 mcg | 5 mg |
| 2 mL | 5 mg/mL | 50 mcg | 2.50 mg |
| 3 mL | 3.33 mg/mL | 33.33 mcg | 1.67 mg |
Worked example: a 10 mg Retatrutide vial in 2 mL of bacteriostatic water is 5 mg/mL. One unit on a U-100 pin is 50 mcg, so if your protocol calls for 2.50 mg you would draw to 50 units. That is arithmetic from the numbers you enter, nothing more. Pepdex does not tell you what dose to take.
Retatrutide reconstitution questions
- How do you reconstitute Retatrutide?
- Add bacteriostatic water to the dry Retatrutide vial slowly down the side, let it dissolve without shaking, and store it in the fridge. The amount of water you add sets the concentration. A 10 mg vial in 2 mL of water is 5 mg/mL; the same vial in 1 mL is 10 mg/mL. Use the calculator above with your own vial and water to see the exact result.
- How many insulin units is a dose of Retatrutide?
- It depends entirely on how much water you mixed, because milligrams describe the powder and units describe the volume drawn. With a 10 mg vial reconstituted in 2 mL, one unit on a U-100 pin is 50 mcg, so 50 units draws 2.50 mg. Change the water and that number changes. Enter your numbers above to get yours.
- What vial sizes does Retatrutide come in?
- Commonly 10 mg, 15 mg, 20 mg. The calculator defaults to 10 mg for Retatrutide but you can set any vial size. Always work from the mg printed on the vial you actually have, not a number from a forum.
- Is retatrutide the same as tirzepatide?
- No. Tirzepatide is a dual agonist (GIP and GLP-1). Retatrutide adds a third target, the glucagon receptor, which is why it is called a triple agonist. They are different molecules and ship in different vial sizes, so the reconstitution numbers are not interchangeable. Run your actual vial through the calculator above.
- Is the Retatrutide calculator free?
- Yes. The reconstitution and units math is completely free with no account. A free account adds saving your protocol plus a 3-day trial of the AI Coach and Personal Stack.
Related calculators
Educational reference only. Pepdex does not sell peptides, recommend vendors, or tell you what dose to take. Retatrutide reconstitution math here is unit conversion you can verify by hand. Talk to a qualified provider about your own use.