Peptide Reconstitution Calculator

Concentration equals the amount in the vial (in mcg) divided by the water added (in mL). The units to draw equal your dose divided by that concentration, multiplied by the syringe's units per mL. Example: a 5 mg vial in 2 mL of water is 2500 mcg/mL, so a 250 mcg dose is 10 units on a U-100 syringe.

Adding water does not change the total peptide in the vial — only the concentration. More water lowers the concentration, so you draw more units for the same dose, which can be easier to read. Common volumes are 1–3 mL. Use the calculator to compare a few volumes side by side.

It depends on the concentration. Divide your dose by the concentration to get the volume in mL, then multiply by the syringe's units per mL (100 for U-100). At 2500 mcg/mL, a 250 mcg dose is 0.1 mL, which is 10 units on a U-100 syringe.

Milligrams (mg) and micrograms (mcg) measure the amount of peptide — 1 mg equals 1000 mcg. Units are marks on an insulin syringe: on a U-100 syringe, 100 units equal 1 mL. This tool converts between the amount you want and the units you draw.

Divide the total amount in the vial (in mcg) by your single dose and round down. A 5 mg vial is 5000 mcg, so at a 250 mcg dose it holds 20 doses. Changing the water volume does not change this count.

No. The amount of peptide per dose stays the same regardless of water volume — only the number of units you draw changes. For the same 250 mcg dose, more water means a higher unit count on the syringe.

Select the calibration printed on the syringe or packaging. U-100 has 100 unit marks per mL and U-40 has 40. A U-100 syringe with a 0.5 mL or 50-unit capacity is still U-100, not U-50.

For informational and educational purposes only. Not medical advice. Peptides are sold for research use only. Consult a licensed healthcare professional before use.