How many units is 2 mg of GHK-Cu?

It depends entirely on how much water you added. In a 50 mg vial reconstituted with 5 mL, the concentration is 10 mg/mL, so 2 mg is 0.2 mL, which is 20 units on a U-100 insulin syringe. In the same vial with 2.5 mL of water it is 10 units, and with 7.5 mL it is 30 units.

How much bacteriostatic water for a 50 mg GHK-Cu vial?

5 mL is the usual choice. It gives 10 mg/mL, which puts the commonly reported range of 1 mg to 5 mg between roughly 10 and 50 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.

How many doses are in a 50 mg vial?

Divide 50 by your dose. At 2 mg that is 25 doses, which at once daily is 25 days.

How many units is 2 mg of GHK-Cu?

In a 50 mg vial with 5 mL of water, 20 units on a U-100 syringe. In the same vial with 2 mL of water, 8 units.

Why is my GHK-Cu blue?

The copper ion. A clear blue solution is expected. Cloudiness or particles are not.

GHK-Cu dosage calculator

GHK-Cu comes in unusually large vials, 50 to 200 mg, and is dosed in whole milligrams.

Peptulator, peptulator.com. Research use only, not medical advice.

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25 printable pages: dosing cards for the twelve most-used compounds at three water volumes, titration planners, a vial log, and five pages on what to do when it has already gone wrong.

Dose to units at the usual vial and water

Dose	U-100 units	Draw	Doses per vial	Vial lasts
1 mg	10 units	0.1 mL	50	50 days
1.5 mg	15 units	0.15 mL	33	33 days
2 mg	20 units	0.2 mL	25	25 days
3 mg	30 units	0.3 mL	16	16 days
4 mg	40 units	0.4 mL	12	12 days
5 mg	50 units	0.5 mL	10	10 days

50 mg vial in 5 mL of bacteriostatic water (10 mg/mL), U-100 insulin syringe, once daily.

About GHK-Cu

GHK-Cu is a naturally occurring copper-binding tripeptide, best known from skincare, and also sold as a lyophilised powder for subcutaneous injection. It is not an approved injectable medicine and is sold for research. The solution is blue; that is the copper, not a problem.

The vials are large, so the arithmetic is different from most peptides. A 50 mg vial with 5 mL of water is 10 mg/mL, so 2 mg is 0.2 mL, or 20 units. Injection-site stinging is widely reported, and a lower concentration (more water) is the usual response to that. Commonly reported doses are 1 to 2 mg daily, sometimes higher.

The same 50 mg vial at other water volumes

If the draw is awkward to read, change the water, not the dose. The dose stays the same; only the mark moves.

Vial	BAC water	Concentration	Draw	U-100 units	Doses/vial
50 mg	2 mL	25 mg/mL	0.08 mL	8 units	25
50 mg	3 mL	16.67 mg/mL	0.12 mL	12 units	25
50 mg	5 mL	10 mg/mL	0.2 mL	20 units	25
100 mg	2 mL	50 mg/mL	0.04 mL	4 units	50
100 mg	3 mL	33.33 mg/mL	0.06 mL	6 units	50
100 mg	5 mL	20 mg/mL	0.1 mL	10 units	50

All rows above assume a 2 mg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.

How long it lasts in the body

Not well characterised in humans. A decay curve is only drawn where a human half-life is documented, so there is none here. Treat any precise figure for GHK-Cu elsewhere with caution.

Common questions

How many units is 2 mg of GHK-Cu?: It depends entirely on how much water you added. In a 50 mg vial reconstituted with 5 mL, the concentration is 10 mg/mL, so 2 mg is 0.2 mL, which is 20 units on a U-100 insulin syringe. In the same vial with 2.5 mL of water it is 10 units, and with 7.5 mL it is 30 units.
How much bacteriostatic water for a 50 mg GHK-Cu vial?: 5 mL is the usual choice. It gives 10 mg/mL, which puts the commonly reported range of 1 mg to 5 mg between roughly 10 and 50 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.
How many doses are in a 50 mg vial?: Divide 50 by your dose. At 2 mg that is 25 doses, which at once daily is 25 days.
How many units is 2 mg of GHK-Cu?: In a 50 mg vial with 5 mL of water, 20 units on a U-100 syringe. In the same vial with 2 mL of water, 8 units.
Why is my GHK-Cu blue?: The copper ion. A clear blue solution is expected. Cloudiness or particles are not.

IndependentThis site does not sell peptides and is not owned by a vendor.

The maths is openThe formula is on every page and in the methodology. The code is one file with an automated test suite, run before each deploy.

How it earnsAffiliate links on one marked page, never inside the calculator.

ReviewedDose ranges and half-lives checked 3 September 2026.

Buying GHK-Cu?

The where to buy page lists the vendors this site uses and what to check first. Peptide Bureau keeps the ranked scorecard.

Where to buyWhat to check before you order Vendor scorecardRanked vendors, at Peptide Bureau Build a full protocolThe stack builder at Peptide Bureau, about two minutes

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Before you use these numbers This is a unit-conversion tool. It turns a vial strength and a water volume into a concentration, a draw volume and a syringe mark. It does not tell you what to take, whether to take it, or whether a compound is safe for you. Most compounds listed are sold for laboratory research and are not approved for human use. Nothing here is medical advice. Dosing decisions belong with a licensed clinician who knows your history. Always check the strength printed on your own vial rather than trusting a preset.