GHK-Cu Reconstitution Calculator: BAC Water, mL and Units

Pick your GHK-Cu vial size and enter how much water you add to see the concentration and how much is in each unit on a U-100 syringe. Enter an amount and it also gives the units to draw. Quick picks are shortcuts for vial sizes; always use the amount printed on your own vial.

GHK-Cu reconstitution table

What different amounts of water give you, for each quick-pick vial size. This is arithmetic, not a recommendation: the right amount of water is whatever makes your measurements easy and matches any instructions you were given.

GHK-Cu concentration by vial size and water added, on a U-100 syringe
Vial	Water	Concentration	Per unit (0.01 mL)	Per 10 units (0.1 mL)
50 mg	2 mL	25 mg/mL	250 mcg	2.5 mg
50 mg	3 mL	16.67 mg/mL	167 mcg	1.67 mg
50 mg	5 mL	10 mg/mL	100 mcg	1 mg
100 mg	2 mL	50 mg/mL	500 mcg	5 mg
100 mg	3 mL	33.33 mg/mL	333 mcg	3.33 mg
100 mg	5 mL	20 mg/mL	200 mcg	2 mg

How the math works for GHK-Cu

A 50 mg GHK-Cu vial holds 50,000 mcg. Mixed with 3 mL of water, that's 50,000 ÷ 3 = 16,667 mcg per mL. One unit on a U-100 syringe is 0.01 mL, so each unit holds 167 mcg. More water spreads the same 50 mg across more units; less water packs it into fewer.

Concentration (mcg per mL) = vial (mg) × 1,000 ÷ water (mL)
mcg per unit = concentration ÷ 100
Units to draw = amount (mcg) ÷ mcg per unit

A peptide vial label with the vial size circled. The mg number is the total amount in the vial, and 1 mg equals 1,000 mcg — Use the mg number printed on your own GHK-Cu vial, not the quick-pick size, if they differ.

What is GHK-Cu?

GHK-Cu is a copper-binding tripeptide (glycine, histidine, lysine) that occurs naturally in human plasma. Topical GHK-Cu is a common skincare ingredient; the FDA's 2026 review is about the injectable form.

Frequently asked questions

How much water do I add to a 50 mg GHK-Cu vial?

There's no single right amount. Less water makes each unit stronger and harder to measure; more water makes each unit weaker and easier to measure. For a 50 mg vial, 2 mL gives 250 mcg per unit, 3 mL gives 167 mcg, and 5 mL gives 100 mcg. If your GHK-Cu was prescribed, use the amount in your prescription instructions.

How many mcg of GHK-Cu are in one unit?

It depends on the vial size and how much water you add: mcg per unit = (mg in the vial × 1,000) ÷ (mL of water × 100). With a 50 mg vial and 3 mL of water, that's 167 mcg per unit on a U-100 syringe.

Is GHK-Cu FDA approved?

No. GHK-Cu isn't an FDA-approved drug. Injectable GHK-Cu was removed from Category 2 in April 2026, with a committee review expected before February 2027. Topical GHK-Cu in skincare is a separate cosmetic product.

Other peptide calculators

General reconstitution calculator · Peptide FDA status tracker