Retatrutide Calculator: Reconstitution, mg/mL & Molarity

Retatrutide (LY3437943) is an investigational 39-amino-acid triple agonist with a C20 fatty diacid side chain, supplied as a lyophilized powder in 5 to 30 mg vials. The calculator uses its molecular weight (4,731.3 g/mol) to report molar concentration alongside mg/mL. Enter the vial size and the volume of bacteriostatic water added to get the concentration, the amount in any measured volume, and how many aliquots a vial yields. For other compounds, use the general peptide calculator.

Retatrutide calculator

—Concentration

—per 0.1 mL (100 µL)

—molar concentration (MW 4,731.3 g/mol)

This tool does solution-concentration arithmetic for laboratory preparation records. It does not provide dosage guidance. Retatrutide is sold for research use only. It is not for human consumption, self-administration or therapeutic use.

Retatrutide vial concentration table

Worked math for each Retatrutide vial size in the catalog (5 mg, 10 mg, 20 mg, 30 mg) with 1, 2 and 3 mL of diluent. The figures come straight from concentration = mass ÷ volume. They are reference arithmetic, not a recommended preparation.

Vial	Diluent	Concentration	Per 0.1 mL	Molarity
Retatrutide 5 mg	1 mL	5 mg/mL	500 mcg	1.06 mM	Load ↑
Retatrutide 5 mg	2 mL	2.5 mg/mL	250 mcg	528 µM	Load ↑
Retatrutide 5 mg	3 mL	1.667 mg/mL	166.7 mcg	352 µM	Load ↑
Retatrutide 10 mg	1 mL	10 mg/mL	1,000 mcg	2.11 mM	Load ↑
Retatrutide 10 mg	2 mL	5 mg/mL	500 mcg	1.06 mM	Load ↑
Retatrutide 10 mg	3 mL	3.333 mg/mL	333.3 mcg	705 µM	Load ↑
Retatrutide 20 mg	1 mL	20 mg/mL	2,000 mcg	4.23 mM	Load ↑
Retatrutide 20 mg	2 mL	10 mg/mL	1,000 mcg	2.11 mM	Load ↑
Retatrutide 20 mg	3 mL	6.667 mg/mL	666.7 mcg	1.41 mM	Load ↑
Retatrutide 30 mg	1 mL	30 mg/mL	3,000 mcg	6.34 mM	Load ↑
Retatrutide 30 mg	2 mL	15 mg/mL	1,500 mcg	3.17 mM	Load ↑
Retatrutide 30 mg	3 mL	10 mg/mL	1,000 mcg	2.11 mM	Load ↑

Retatrutide compound data used in the math

Compound class	39-amino-acid acylated GIP / GLP-1 / glucagon receptor triple agonist
Molecular weight	4,731.3 g/mol
Molecular formula	C₂₂₁H₃₄₂N₄₆O₆₈
CAS number	2381089-83-2
Appearance	White to off-white lyophilized powder; clear, colorless solution
Storage	Lyophilized: −20 °C, desiccated, protected from light. Reconstituted: 2–8 °C.
Vial sizes	5 mg, 10 mg, 20 mg, 30 mg

Molar concentration (mM) = concentration (mg/mL) ÷ molecular weight (g/mol) × 1000. Every product ships with a certificate of analysis. See the Retatrutide product page or the COA portal.

Retatrutide reconstitution handling notes

The 30 mg vial reconstituted with 3 mL (about the most a standard 3 mL vial holds) gives 10 mg/mL. More dilute preparations need a larger sterile vial.
Retatrutide is an investigational compound with no approved product labeling. Preparation parameters come only from the researcher’s protocol; this page does arithmetic, not recommendations.
Swirl gently until the solution is completely clear. Persistent cloudiness after gentle mixing points to incomplete dissolution or degraded material, and that lot’s certificate of analysis should be checked.

For the full bench procedure, including materials, technique, blend vials and storage before and after, see how to reconstitute peptides.

How to reconstitute Retatrutide

The worked example uses a 10 mg Retatrutide vial and 2 mL of bacteriostatic water. The same steps apply to any vial size or volume; only the resulting concentration changes.

Equilibrate and sanitize. Let the Retatrutide vial and the bacteriostatic water reach room temperature, then wipe both rubber stoppers with an alcohol swab.
Draw the diluent. With a sterile syringe, withdraw 2 mL of bacteriostatic water.
Add it slowly down the wall. Insert the needle through the Retatrutide vial’s stopper and let the water run down the inside of the glass, not directly onto the powder.
Swirl, don’t shake. Rotate the vial gently until the solution is completely clear and colorless. Cloudiness or particles after gentle mixing are a reason to check the lot’s certificate of analysis.
Label and store. Write the concentration on the vial: 10 mg ÷ 2 mL = 5 mg/mL (1.06 mM), plus the date and lot number. Storage: Lyophilized: −20 °C, desiccated, protected from light. Reconstituted: 2–8 °C.

Retatrutide reconstitution FAQ

What concentration does a 5 mg Retatrutide vial make with 2 mL of bacteriostatic water?

5 mg divided by 2 mL is 2.5 mg/mL, which is 250 mcg in every 0.1 mL. Using Retatrutide’s molecular weight of 4,731.3 g/mol, that is a molar concentration of 528 µM.

How much Retatrutide is in 0.1 mL after reconstitution?

It depends entirely on the concentration prepared. For example, a 10 mg vial reconstituted with 2 mL gives 5 mg/mL, so 0.1 mL contains 500 mcg. The same vial reconstituted with 1 mL would give twice that per 0.1 mL.

Does adding more bacteriostatic water change how much Retatrutide is in the vial?

No. The diluent volume only sets the concentration. The total Retatrutide in the vial is the same whatever volume is added. More diluent spreads it across a larger volume, so any given amount takes up more mL and is easier to measure accurately.

How should reconstituted Retatrutide be stored?

Lyophilized: -20 °C, desiccated, protected from light. Reconstituted: 2-8 °C. Label the vial with the compound, lot number, date and the concentration calculated here.