Peptide Calculator

The calculator first determines the solution concentration from the amount of peptide in the vial and the volume of diluent added. It then uses the amount to be converted to determine the solution volume in millilitres and the corresponding mark on the U-100 scale. It also displays the result on an illustration of a syringe.

concentration in µg/ml = (mg in vial × 1,000) ÷ ml of diluent
U-100 scale mark = (requested µg ÷ concentration in µg/ml) × 100

No. The calculator performs a mathematical conversion of the entered values only. It does not assess product quality, health status or whether a substance is approved, safe or suitable for a particular person. The result is not a dose recommendation or instructions for use.

Milligrams (mg) and micrograms (µg or mcg) describe the amount of peptide; 1 mg equals 1,000 µg. Millilitres (ml) describe liquid volume. A number on the U-100 scale is an insulin-syringe calibration, not a unit of peptide. A syringe mark therefore cannot be converted into micrograms without knowing the concentration.

Reconstitution means preparing a solution from a lyophilised, or freeze-dried, peptide using a suitable diluent. The type and volume of diluent, as well as the reconstitution conditions, vary by product. Some products require sterile water, saline or their own supplied diluent. Always follow the documentation for the specific product.

U-100 denotes a scale intended for insulin at a concentration of 100 insulin units in 1 ml. On this scale, mark 10 corresponds to a volume of 0.1 ml and mark 100 to a volume of 1 ml. The calculator uses these numbers only as an aid for measuring volume; they are not peptide units. The volume-to-mark conversion cannot be used for U-40, U-500 or any other scale.

The volume of diluent changes the concentration, not the total amount of peptide in the vial. More diluent means a lower concentration and a larger volume for the same amount of peptide. The combinations below are mathematical examples only, not recommendations for how much diluent to add; the correct type and volume are specified in the documentation for the specific product.

Bacteriostatic Water for Injection contains a preservative, usually 0.9–1.1% benzyl alcohol. This allows repeated withdrawals from the vial for the period specified by the manufacturer, provided aseptic handling is followed. Sterile Water for Injection contains no preservative, so any remainder must not be reused after opening. The two are not universally interchangeable, and benzyl alcohol poses a particular risk to neonates. Use only the diluent specified in the documentation for the specific product.

Shelf life and storage temperature cannot be determined in general. They vary according to the specific substance, solution composition and product. Follow its official documentation only; if it does not provide storage conditions, do not estimate the shelf life.

A lyophilised form is generally more stable than a solution, but there is no universal storage temperature or shelf life. Some products require freezing, while others require refrigeration or room temperature and may be damaged by freezing. Always follow the label and official documentation for the specific product.

A volume smaller than the smallest graduation on the selected syringe may not be measured reliably. If the calculated volume exceeds its capacity, it cannot be measured in one draw. Do not estimate the result or change the dilution yourself; recheck the inputs and the procedure for the specific product.