Peptide reconstitution calculator
Tell it what your vial says and how much you want per draw. It works out how much bacteriostatic water to add, and which line on your syringe that lands on. No account, no email, nothing leaves your browser.
Peptide
Amount per vial
Standard size
Target quantity per draw · GHK-Cu
Each button splits the vial into that many equal draws
These buttons are just division. Each one splits the vial into equal draws. They are not a suggestion of how much to take.
Syringe
Empty on purpose. We don’t pick an amount for anyone, so nothing is pre-selected. Tap a button above and the vial and the syringe fill in.
The words
What reconstitution means
Your vial holds freeze-dried powder. Reconstituting it means adding bacteriostatic water so the powder dissolves and you can measure it with a syringe. That is the whole word. Some labels call the powder lyophilized, which is the same thing.
The one thing worth knowing before you start: once the water is in, it cannot come back out. That is why this calculator runs before you open anything. The step-by-step
The arithmetic
It is two divisions, and the first one decides everything.
Milligrams in the vial, divided by millilitres of water, gives you strength. Then the amount you want, divided by that strength, gives you the volume to draw.
A 5 mg vial, two ways
Add 2 mL of water: 5 ÷ 2 = 2.5 mg/mL. A 0.5 mg draw is 0.5 ÷ 2.5 = 0.20 mL, which is 20 units on a U-100 syringe.
Add 5 mL instead: 5 ÷ 5 = 1 mg/mL. The same 0.5 mg draw is now 0.50 mL — 50 units.
Same vial, same 0.5 mg, two and a half times the liquid. The water is the choice that decides everything downstream.
Why this one runs backwards
The water is the answer, not the question.
Most calculators ask how much water you added and hand back a number like 6.4 units. No syringe can be read to 6.4. You end up eyeballing a mark that does not exist.
But you choose the water before you mix, so it is the number worth getting right. This one checks every line printed on your syringe, throws out the volumes that overfill the vial or leave powder undissolved, and picks one that lands on a mark you can actually see.
What that looks like
A 70 mg Glow vial holds 50 mg of GHK-Cu. Add 2.50 mL and a 2 mg draw is exactly 10 units. Add 3 mL and the same 2 mg becomes 12 units.
Both are correct. One is a numbered line you can read across the room. That is the entire reason to solve for the water.
Limits
What it will not do.
It will not pick an amount for you.
You type in how much you want per draw. The preset buttons are just division — each one splits the vial into equal draws. None of it is a suggestion of how much to take.
It will not guess at a number we cannot source.
Where a component has no sourced solubility figure, the calculator will not solve for the water at all. It asks you for the volume instead and says why.
It will not print a use-by date.
We could not find a shelf-life figure that covers a mixed vial in a household fridge, so there is no expiry countdown anywhere on this site.
Per blend
Pre-filled with what is in each vial.
Only three blends are live so far. We add a compound once we can source what is in it and how much dissolves. Never before that.