Peptide Reconstitution Calculator

Find the exact number of units to draw for your target dose.

Syringe volume

Peptide vial mass (mg)

BAC water used (mL)

Draw 5 units (0.05 mL) for a 250 mcg dose.

Warning: The required draw exceeds your selected syringe volume.

0 30 u

Quick converters

Micrograms ↔ Milligrams

Milliliters ↔ Units

Peptide reconstitution reference

How this calculator works

The calculator converts a vial's peptide mass and the bacteriostatic (BAC) water added into the volume to draw on an insulin syringe. First it finds the concentration, then the volume for your dose:

units to draw = (dose mg ÷ (vial mg ÷ BAC water mL)) × 100

The ×100 converts millilitres to insulin-syringe units, since 1 unit = 0.01 mL on a U-100 syringe. Worked example: a 5 mg vial reconstituted with 2 mL of BAC water gives 2.5 mg/mL; a 250 mcg (0.25 mg) dose is 0.25 ÷ 2.5 = 0.1 mL, i.e. 10 units.

Units & conversions

Doses are entered in micrograms or milligrams, where 1 mg = 1000 mcg. Syringe volume relates to draw as 1 mL = 100 units, so 0.01 mL = 1 unit. The on-page converters handle mcg–mg and mL–unit conversions directly.

Choosing your BAC water volume

Reconstitution volume sets concentration, not the total dose available. A larger BAC volume lowers concentration and increases the units drawn for the same dose, which can improve measurement precision on the syringe. A smaller volume concentrates the peptide into fewer units.

Reading the syringe

Use a U-100 insulin syringe and read the dose in units, not millilitres: each unit mark equals 0.01 mL. Choose a syringe whose capacity is close to your draw so the markings you use are well spaced.

Storing reconstituted peptides

Once reconstituted, most peptides are refrigerated and used within a defined stability window; light and repeated temperature cycling degrade them. See PepRecon's bacteriostatic water stability data for the measured findings.

Which calculator should I use?

Use this calculator for peptides dosed by mass (mcg or mg). For growth hormone dosed in IU, use the HGH Reconstitution & Dosage Calculator. To solve for the BAC water that yields a specific draw size, use the Reverse Peptide Calculator. For several peptides in one vial, use the Peptide Blend Calculator.

Data handling and privacy

Calculations run in your browser. Values are not transmitted or stored unless you explicitly generate a share link.

Scope & safety

PepRecon is a research and education resource. This calculator and reference material are provided for informational purposes and are not medical advice; they do not establish a dosing recommendation. Consult a qualified clinician before use.