Peptide Reconstitution Calculator
Work out the concentration of a reconstituted vial and exactly how many units to draw on a U-100 insulin syringe. Enter the amount in the vial, the bacteriostatic (BAC) water you add, and your amount per dose.
Optional. Enter your own amount to see the draw.
Enter the amount in the vial and the liquid added to see the concentration.
This is arithmetic on your inputs. VialVine doesn’t suggest amounts or preparation methods. Double-check every calculation.
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How the reconstitution math works
- Concentration (mg/mL) = amount in the vial (mg) ÷ liquid added (mL).
- Volume to draw (mL) = amount per dose (mg) ÷ concentration.
- Units on a U-100 syringe = volume (mL) × 100, because a U-100 syringe holds 100 units per mL.
- Example: 10 mg with 2 mL of BAC water is 5 mg/mL. A 0.25 mg dose is 0.05 mL, or 5 units. That vial holds 40 doses of 0.25 mg.
Frequently asked questions
How many units is 0.25 mg on an insulin syringe?
It depends on the concentration. At 5 mg/mL (10 mg in 2 mL), 0.25 mg is 0.05 mL, which is 5 units on a U-100 syringe. Enter your own numbers above to see yours.
What is a U-100 syringe?
A U-100 insulin syringe is marked in units where 100 units equal 1 mL. Common sizes are 0.3 mL (30 units), 0.5 mL (50 units) and 1 mL (100 units).
How much bacteriostatic water should I add?
That's your choice; the calculator doesn't recommend an amount. More liquid lowers the concentration, which makes each draw larger and easier to measure. Less liquid makes each draw smaller.
Does it work in mcg?
Yes. Switch the vial or dose unit to mcg. 1 mg = 1,000 mcg.