Peptide Dosage & Units Calculator
Once a vial is mixed, the practical question is: how many units do I pull? This calculator converts a dose in micrograms into the exact mark on a U-100 insulin syringe, and tells you how many doses the vial holds.
The formula
Volume (mL) = dose ÷ concentration
Units = volume × 100 (U-100 syringe)
Units = volume × 100 (U-100 syringe)
The ×100 step is just the definition of a U-100 syringe: 100 units fill one millilitre.
Worked example
Example
Concentration of mix2,500 mcg/mL
Desired dose250 mcg
Volume to draw0.1 mL
On a U-100 syringe10 units
How to use the calculator
- Enter your vial strength and the water you added to set the concentration.
- Enter your desired dose in mcg or mg.
- Read the big number — that's the units to draw. You'll also see the volume in mL and how many doses are in the vial.
- Pick your syringe size; the tool warns you if a dose won't fit in one draw.
Frequently asked questions
How do I convert a peptide dose to insulin units?
First divide your dose by the mix's concentration to get the volume in millilitres. Then multiply by 100, because a U-100 insulin syringe is marked with 100 units per millilitre. For example, a 250 mcg dose from a 2,500 mcg/mL mix is 0.1 mL, which equals 10 units.
What does U-100 mean on an insulin syringe?
U-100 means the syringe is graduated so that 100 units equals one millilitre. This holds whether the syringe's total capacity is 0.3 mL, 0.5 mL, or 1 mL — the unit markings represent the same volume per unit. So units equal millilitres multiplied by 100.
How many doses are in my vial?
Divide the total peptide in the vial by your dose, keeping the units consistent. A 5 mg (5,000 mcg) vial dosed at 250 mcg gives 20 doses. The calculator shows this automatically.
My dose is only a couple of units — is that a problem?
Very small draws are hard to measure precisely, so small errors become large percentage errors. Reconstituting with more bacteriostatic water lowers the concentration so the same dose occupies more units on the syringe and is easier to read accurately.