Tool Reconstitution calculator
Peptide Calculator: Reconstitution, Units and Syringe Draw
Concentration is vial milligrams divided by water milliliters; syringe units are draw volume in mL times 100 on a U-100 syringe. Type your three numbers and the calculator shows the result and the arithmetic behind it.
Your numbers
This page does arithmetic. It does not tell you what amount to use, how often, or how much water to add. Those are questions for a licensed clinician, and the reasons are in the methodology.
Result
How this was calculated
01 Method
How the math works
Three divisions and one multiplication. Nothing here depends on which peptide is in the vial.
| Quantity | Formula |
|---|---|
| Concentration (mg/mL) | vial mg / water mL |
| Draw volume (mL) | draw mg / concentration |
| Units on a U-100 syringe | draw mL x 100 |
| Draws per vial | vial mg / draw mg |
Micrograms convert to milligrams by dividing by 1,000 first. A U-100 insulin syringe is graduated at 100 units per milliliter under ISO 8537, so a 1 mL syringe holds 100 units, a 0.5 mL syringe holds 50, and a 0.3 mL syringe holds 30.
Worked examples
Example 1
5 mg vial, 2 mL water, 250 mcg draw, 1 mL syringe.
5 / 2 = 2.5 mg/mL. 250 mcg = 0.25 mg. 0.25 / 2.5 = 0.1 mL. 0.1 x 100 = 10 units. 5 / 0.25 = 20 draws.
Example 2
10 mg vial, 1 mL water, 1 mg draw, 1 mL syringe.
10 / 1 = 10 mg/mL. 1 / 10 = 0.1 mL. 0.1 x 100 = 10 units. 10 / 1 = 10 draws.
Example 3
2 mg vial, 1 mL water, 100 mcg draw, 1 mL syringe.
2 / 1 = 2 mg/mL. 100 mcg = 0.1 mg. 0.1 / 2 = 0.05 mL. 0.05 x 100 = 5 units. 2 / 0.1 = 20 draws.
These three cases are the calculator's test suite. The page is not deployed unless all three pass, and you can check any of them by typing the inputs above.
02 Units
Unit conversion table
| Volume | Units (U-100) | Fits in |
|---|---|---|
| 0.01 mL | 1 | any insulin syringe |
| 0.05 mL | 5 | any insulin syringe |
| 0.10 mL | 10 | any insulin syringe |
| 0.30 mL | 30 | 0.3, 0.5 or 1 mL syringe |
| 0.50 mL | 50 | 0.5 or 1 mL syringe |
| 1.00 mL | 100 | 1 mL syringe |
Mass: 1 mg = 1,000 mcg (micrograms). Some labels write mcg as µg; they are the same unit.
03 Questions
Questions people ask
How do you calculate peptide concentration after reconstitution?
Divide the milligrams in the vial by the milliliters of water you added. A 5 mg vial with 2 mL of water is 5 / 2 = 2.5 mg/mL.
How many units is a draw on an insulin syringe?
A U-100 insulin syringe is marked at 100 units per mL, so multiply the volume in mL by 100. A 0.1 mL draw is 10 units; a 0.05 mL draw is 5 units.
How many draws are in a vial?
Divide the vial's total milligrams by the milligrams per draw. A 5 mg vial at 0.25 mg per draw yields 20 draws.
Does this calculator suggest a dose?
No. It only converts the numbers you type. PeptideGauge publishes no dosing, scheduling or bacteriostatic water guidance, and the presets set vial size only. The methodology page explains what the site leaves out and why.
What if the draw does not fit on my syringe?
The result panel flags it. A 0.3 mL syringe tops out at 30 units; a draw above that needs a larger syringe or a different concentration, and the concentration is set by the water volume you chose.
Is anything I type stored?
No. The calculator runs entirely in your browser and makes no network request with your numbers.
Every number on this site comes with the arithmetic or the document behind it.
Read the methodology