About Retatrutide
Retatrutide (research code LY3437943) is a synthetic peptide studied as an agonist at three receptors: GIP, GLP-1 and glucagon. It is often listed as “Reta” or “GLP-3”. Biogenesis Labs supplies retatrutide as lyophilized (freeze-dried) powder in 30 mg and 40 mg vials, for laboratory research use only.
Research-grade vials: Retatrutide 30 mg · Retatrutide 40 mg. Every batch is independently tested — see the Certificates of Analysis.
How to calculate Retatrutide concentration
concentration (mg/mL) = retatrutide in vial (mg) ÷ diluent volume (mL)
- A 30 mg Retatrutide vial with 2 mL of bacteriostatic water is 15.00 mg/mL (15,000 mcg/mL).
- On a U-100 syringe, 100 units = 1 mL, so each unit holds 150.0 mcg.
- Use 3 mL instead and the same vial reads 10.00 mg/mL, or 100.0 mcg per unit. More diluent lowers the concentration; the retatrutide in the vial does not change.
For U-40 syringes (40 units = 1 mL), divide mcg/mL by 40 instead of 100. The calculator above switches between both scales.
Retatrutide reconstitution chart
Concentration for each Biogenesis Labs vial size across common diluent volumes. “In 10 units” is the retatrutide contained in 10 units on a U-100 syringe (0.10 mL).
Retatrutide 30 mg vial
| Diluent | Concentration | mcg / mL | Per U-100 unit | In 10 units | U-100 units per 1 mg |
|---|---|---|---|---|---|
| 1 mL | 30.00 mg/mL | 30,000 | 300.0 mcg | 3.00 mg | 3.33 |
| 1.5 mL | 20.00 mg/mL | 20,000 | 200.0 mcg | 2.00 mg | 5.00 |
| 2 mL | 15.00 mg/mL | 15,000 | 150.0 mcg | 1.50 mg | 6.67 |
| 2.5 mL | 12.00 mg/mL | 12,000 | 120.0 mcg | 1.20 mg | 8.33 |
| 3 mL | 10.00 mg/mL | 10,000 | 100.0 mcg | 1.00 mg | 10.00 |
| 4 mL | 7.50 mg/mL | 7,500 | 75.0 mcg | 0.75 mg | 13.33 |
| 5 mL | 6.00 mg/mL | 6,000 | 60.0 mcg | 0.60 mg | 16.67 |
Retatrutide 40 mg vial
| Diluent | Concentration | mcg / mL | Per U-100 unit | In 10 units | U-100 units per 1 mg |
|---|---|---|---|---|---|
| 1 mL | 40.00 mg/mL | 40,000 | 400.0 mcg | 4.00 mg | 2.50 |
| 1.5 mL | 26.67 mg/mL | 26,667 | 266.7 mcg | 2.67 mg | 3.75 |
| 2 mL | 20.00 mg/mL | 20,000 | 200.0 mcg | 2.00 mg | 5.00 |
| 2.5 mL | 16.00 mg/mL | 16,000 | 160.0 mcg | 1.60 mg | 6.25 |
| 3 mL | 13.33 mg/mL | 13,333 | 133.3 mcg | 1.33 mg | 7.50 |
| 4 mL | 10.00 mg/mL | 10,000 | 100.0 mcg | 1.00 mg | 10.00 |
| 5 mL | 8.00 mg/mL | 8,000 | 80.0 mcg | 0.80 mg | 12.50 |
Values are rounded. Figures describe solution concentration only and are not recommendations.
Reconstituting and storing a Retatrutide vial
Let the sealed vial reach room temperature, swab both stoppers, and run the diluent slowly down the inside wall of the vial rather than onto the powder. Swirl gently until dissolved — don't shake — and label the vial with the concentration and date. Reconstituted solutions are commonly kept refrigerated at 2–8 °C and protected from light. The full step-by-step guide, syringe-scale explainer and BAC vs. sterile water comparison are on the main Peptide Calculator page.
Retatrutide calculator FAQ
What concentration does a 30 mg Retatrutide vial with 3 mL of bacteriostatic water give?
10.00 mg/mL (10,000 mcg/mL). On a U-100 syringe that is 100.0 mcg per unit, and 10 units hold 1.00 mg.
What concentration does a 30 mg Retatrutide vial with 2 mL give?
15.00 mg/mL, or 150.0 mcg per unit on a U-100 syringe.
And a 40 mg Retatrutide vial with 2 mL?
20.00 mg/mL, or 200.0 mcg per unit on a U-100 syringe.
How many U-100 units contain 1 mg of Retatrutide?
It depends on the concentration: units per mg = 100 ÷ concentration in mg/mL. At 10.00 mg/mL (30 mg in 3 mL) 1 mg is in 10.00 units; at 15.00 mg/mL (30 mg in 2 mL) it is in 6.67 units.
How much bacteriostatic water should be added to a Retatrutide vial?
There is no single correct volume. The volume comes from your own research protocol; the calculator and chart show the concentration each volume produces. Only add a volume your vial can hold.
Is GLP-3 the same as retatrutide?
On Biogenesis Labs listings, “GLP 3” and “Reta” both refer to retatrutide. The calculator math is the same whichever name is on the label; what matters is the mg printed on the vial.
Does this Retatrutide calculator provide dosing guidance?
No. It performs concentration and unit-conversion math only. All Biogenesis Labs products are supplied for laboratory research use only and are not for human consumption.
