Educational reference only — not medical advice. This calculator does maths only and does not recommend any dose. Always confirm your dose and preparation with a licensed healthcare provider or pharmacist.
Reconstitution Calculator
Results update live as you type. Your dose must come from your prescription or provider — this tool never suggests one.
Printed on the vial label — the total powder in the vial.
The volume of bacteriostatic water you mix into the vial.
Enter the dose exactly as given to you. 1 mg = 1,000 mcg.
U-100 syringes: 100 units = 1 mL, whatever the barrel size.
Nothing you type leaves this page — the calculation runs entirely in your browser. Educational reference only, not medical advice.
GHK-Cu is the heavyweight of this site — literally. Its vials hold ten to forty times the powder of a typical peptide vial, which means the concentrations are far higher and a normal-looking amount can be just a few syringe units. This page is mostly a warning about that scale, followed by the same formula as everywhere else.
What is GHK-Cu?
GHK-Cu (Copper Tripeptide-1) is the copper(II) complex of a tripeptide: glycine-histidine-lysine (GHK) attached to a copper ion. GHK occurs naturally in human plasma — the parent tripeptide was isolated from human plasma in 1973 — and its concentration in plasma is reported to decline with age. It is sold as a blue freeze-dried powder (the colour comes from the copper) for injectable/research formats, and also as topical cosmetic serums and powders — a separate format. This calculator page is for the lyophilised injectable/research vial format only. The mixed solution is characteristically faint blue or blue-green, which is normal for the copper complex and has no effect on the maths.
It is not FDA-approved as a drug for any therapeutic indication. The cosmetic form (Copper Tripeptide-1) is sold over the counter in topical skincare, but that is a different regulatory category and does not establish approval for injectable use. Injectable/research forms are not FDA-approved. (Compounding note: GHK-Cu was added to the FDA 503A Category 1 list for non-injectable routes only in 2026; nominations for injectable GHK-Cu were withdrawn in April 2026. That is a compounding-list change, not drug approval.)
The vial maths.
Standard research vials are 50 mg and 100 mg, with 200 mg also sold. Because the vials hold far more powder than most peptides, their concentrations after mixing are much higher and an amount may be only a few syringe units — which is hard to measure accurately. Adding more water lowers the concentration so the same amount becomes more units; any change to your mix should be confirmed with your provider or pharmacist first.
Worked example — 50 mg vial, 2 mL of BAC water, example amount 1,000 mcg (1 mg):
- Concentration: (50 × 1,000) ÷ 2 = 25,000 mcg/mL
- Each unit holds 25,000 ÷ 100 = 250 mcg
- Units for the example amount: 1,000 ÷ 250 = 4 units (0.04 mL)
- Amounts in the vial: 50,000 ÷ 1,000 = 50 amounts
Four units is a very small draw. On a 1 mL syringe with 2-unit marks, that is only two marks — a 0.3 mL syringe with finer marks reads it more accurately. If your amount works out to only a few units, double-check the vial size and the water volume before drawing anything.
Storage (commonly cited):
Unmixed vial in the freezer (ideally below −20 °C), or refrigerated at 2–8 °C, dry and dark. Once mixed, refrigerate at 2–8 °C, protect from light, do not freeze. Usable window varies by source — most commonly “up to 28 days”, with some sources saying 14–28 days, 28–60 days, or 4–6 weeks. Do not treat any single figure as settled.
FAQs
What is the concentration of a 50 mg GHK-Cu vial in 2 mL?
50 × 1,000 ÷ 2 = 25,000 mcg/mL, so each unit contains 250 mcg. That means even a 1,000 mcg example amount is only 4 units at this mix — which is why the calculator warns about very small draws.
My GHK-Cu amount works out to only a few units. Is that right?
It can be, because the vials are large and the concentration is high. A few units is hard to measure accurately, though: adding more water lowers the concentration so the same amount becomes more units. Any change to your mix should be confirmed with your provider or pharmacist first.
Why is the GHK-Cu solution blue?
The copper ion in the complex gives both the powder and the mixed solution a characteristic blue colour. The colour has no effect on the maths — concentration still depends only on the labelled mg and the water volume.
Is GHK-Cu FDA-approved?
Not as a drug, for any use. The cosmetic topical form is sold over the counter, but that is not approval for injectable use.
Related calculators
See also the MOTS-C Calculator and the Peptide Calculator home page.
Educational reference only — not medical advice. This calculator does maths only and does not recommend any dose. Always confirm your dose and preparation with a licensed healthcare provider or pharmacist.