Peptide Reconstitution
Calculator
Enter your vial size, the bacteriostatic water you added and a target amount. This calculator returns the exact concentration, the volume to measure and the units to read on a graduated syringe scale, live. Pure reconstitution math, no guesswork.
Your vial
Pick a Genix vial to auto-fill its size, or choose custom for any peptide.
The total peptide mass printed on the vial or Certificate of Analysis.
How much solvent you reconstitute with. More water means a lower concentration.
The amount you want in each draw. 1000 mcg equals 1 mg.
Most research uses a U-100 graduated syringe, where 100 units equal 1 mL.
Measure this
Reconstitution mathNumbers update live and are reconstitution arithmetic only. Genix research materials are for laboratory research use, not for human or veterinary use. Nothing here is medical advice, a dosing recommendation or an instruction for administration.
How peptide reconstitution works
Every reconstituted peptide comes down to one idea: concentration. Once you know how much peptide sits in each millilitre, the syringe reading is simple arithmetic.
Find the concentration
Divide the peptide mass in the vial by the millilitres of bacteriostatic water you add. A 5 mg vial in 2 mL of water is 2.5 mg per mL.
Find the volume
Divide your target amount by that concentration. A 500 mcg (0.5 mg) amount at 2.5 mg per mL needs 0.2 mL drawn into the syringe.
Convert to units
Multiply the volume by 100 for a U-100 syringe. 0.2 mL becomes 20 units, so you measure the plunger to the 20 mark. That is the whole calculation.
The 100 is the U-100 syringe scale, where 100 units fill 1 mL. Swap in 40 for a U-40 syringe. The calculator above handles the conversion for whichever syringe you pick.
Common vials, done for you
Four setups researchers reach for most. Each row is exactly what the calculator returns, so you can sanity-check your own numbers against them.
| Vial | Water | Amount | Concentration | Volume | Units (U-100) | Draws |
|---|---|---|---|---|---|---|
| 5 mg | 2 mL | 500 mcg | 2.5 mg/mL | 0.20 mL | 20 units | 10 |
| 10 mg | 2 mL | 250 mcg | 5.0 mg/mL | 0.05 mL | 5 units | 40 |
| 10 mg | 3 mL | 1 mg | 3.33 mg/mL | 0.30 mL | 30 units | 10 |
| 100 mg | 5 mL | 2 mg | 20 mg/mL | 0.10 mL | 10 units | 50 |
U-100 vs U-40, and why it matters
The scale printed on your syringe decides what a unit means. Reading the wrong scale is the single most common reconstitution error, so confirm it before you measure.
Peptide calculator questions
First find the concentration: divide the peptide mass in the vial by the millilitres of bacteriostatic water you added. That gives mg per mL. Divide your target amount by that concentration to get the volume to draw, then multiply by 100 for the units on a U-100 syringe scale. This tool does that math for you.
There is no single correct amount. More water lowers the concentration, so each unit on the syringe holds less peptide and small amounts are easier to measure. Less water concentrates it. Common research volumes are 1 to 3 mL. Enter any volume above and the calculator recalculates the draw instantly.
It depends entirely on the concentration. Reconstitute a 5 mg vial with 2 mL of water and you get 2.5 mg per mL, so 250 mcg is 0.1 mL, which is 10 units on a U-100 syringe. Change the vial size or water volume and the unit count changes. Use the calculator to match your own vial.
U-100 describes the scale: 100 units equal 1 mL, so one unit is 0.01 mL. It is the most common graduated syringe used for reconstituted peptides. A U-40 syringe uses a different scale where 40 units equal 1 mL. Pick your syringe type in the calculator so the unit reading is correct.
Divide the total peptide mass in the vial by your target amount per draw. A 10 mg vial at 500 mcg gives 20 full draws. Bacteriostatic water does not change the number of draws, only the volume and unit count per draw. The calculator shows draws per vial automatically.
No. The amount of peptide in each draw depends on the volume you pull, not the total water. More water simply spreads the same peptide across more liquid, so you draw more units for the same amount. It can make small amounts easier to measure accurately on the syringe scale.
No. Genix research materials are sold for laboratory research use only and are not for human or veterinary use. This calculator performs reconstitution arithmetic for research planning and does not provide medical guidance or a dosing recommendation. For anything involving your health, speak with a qualified healthcare professional.
This calculator performs reconstitution arithmetic to help plan laboratory research. It is not medical advice, not a dosing recommendation, not an instruction for administration and not a substitute for professional guidance. Every product sold by Genix Labs is intended strictly for laboratory research use and is not for human or veterinary use. Always confirm the peptide mass against the batch Certificate of Analysis and handle all materials according to your own safety protocols.
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