GHK-Cu Reconstitution Calculator (mg → units)
A 50 mg vial of GHK-Cu mixed with 2 mL of bacteriostatic water holds 25,000 mcg/mL, so a 2 mg dose is 0.08 mL — 8 units on a U-100 insulin syringe. Change the vial, water or dose below, or read the chart for other mixes.
GHK-Cu dilution chart: 2 mg in units
| Vial | + 1 mL water | + 2 mL water | + 3 mL water | Doses per vial |
|---|---|---|---|---|
| 50 mg | 4 U 0.04 mL · 50,000 mcg/mL | 8 U 0.08 mL · 25,000 mcg/mL | 12 U 0.12 mL · 16,667 mcg/mL | 25 |
| 100 mg | 2 U 0.02 mL · 100,000 mcg/mL | 4 U 0.04 mL · 50,000 mcg/mL | 6 U 0.06 mL · 33,333 mcg/mL | 50 |
1 mL = 100 units on a U-100 syringe. Water volume changes the units per dose, never the number of doses in the vial.
Measuring GHK-Cu: the math that matters
GHK-Cu vials are unusually large, typically 50 mg or 100 mg, so the solution ends up very concentrated and any single draw is tiny. A 50 mg vial mixed with 2 mL of bacteriostatic water holds 25,000 mcg/mL. An example amount of 2 mg is then 0.08 mL, or 8 units on a U-100 syringe. From a 100 mg vial with the same 2 mL it is 4 units, and with only 1 mL it falls to 2 units, a single line on most 1 mL syringes.
That makes GHK-Cu the opposite of TB-500: here the risk is a draw so small that one line of error is a large fraction of the dose. More water helps. A 100 mg vial with 3 mL brings 2 mg up to 6 units; the chart shows that even the most dilute mix listed stays under 13 units. If the draw is still below about 10 units, a 0.3 mL or 0.5 mL insulin syringe, which usually has finer markings, is easier to read than a 1 mL one.
Large vials also mean many draws from the same stopper. A 100 mg vial holds 50 portions of 2 mg, far more than most peptide vials, so the vial is punctured and stored for longer. That is the case the injection guide's advice on labelling, refrigeration and discarding cloudy solutions is written for.
Most GHK-Cu use is topical, where strength is written as a percentage rather than a dose. The arithmetic is simple: 1% weight per volume is 10 mg per mL, so 0.1% is 1 mg/mL and 2% is 20 mg/mL. A 50 mg vial in 2 mL is 2.5%. The calculator's concentration figure in mcg/mL divided by 10,000 gives the percentage.
Common GHK-Cu measuring mistakes
- Reconstituting a 100 mg vial with 1 mL and trying to measure 2 units by eye.
- Confusing percent and mg/mL. A 1% serum is 10 mg/mL, not 1 mg/mL.
- Assuming a GHK-Cu vial is the same size as other peptide vials. At 50–100 mg it is five to ten times larger, and the units change accordingly.
- Treating the example amount on this page as a recommended dose. No injectable dose is established.
- Keeping a large multi-dose vial unlabelled for weeks and losing track of when it was mixed.