GHK-Cu reconstitution calculator.
GHK-Cu is the awkward one, because it is sold two completely different ways. Cosmetic and topical use buys it in bulk 50 mg and 100 mg vials, while injectable research vials are often 1 mg to 2 mg, and a calculator preset for one is useless for the other. Set the vial size you actually have first, then everything downstream is fixed.
Reference range often cited for GHK-Cu: 1000–2000 mcg, shown for orientation only, not a recommendation. Enter your own target below. Read the evidence →
⚠ Highly concentrated solution: each unit holds a lot of peptide, so small marking differences represent large amount differences.
⚠ Very small draw volume: measurement error risk may be higher.
Each unit on a 100u · 1.0 mL syringe ≈ 250 mcg of this solution.
Show the math
More water → lower concentration → more units for the same amount.
What changes the math for GHK-Cu.
- A 50 mg vial in 5 mL is 10,000 mcg/mL. A 1 mg vial in 1 mL is 1,000 mcg/mL. That is a tenfold difference in what a single syringe unit contains, from the same compound name.
- Reconstituted GHK-Cu is visibly blue, because the peptide is complexed with copper. That tint is expected and is not a contamination signal, but it does mean spills stain.
- For topical preparation the target is usually a percentage rather than a per-draw amount. 50 mg into 5 mL of vehicle is 1% by weight per volume, which is why bulk vials and round water volumes go together.
Formats and worked examples.
How GHK-Cu is actually administered, with the concentration arithmetic written out. Amounts in these tables are illustrative examples of the math, never a recommendation.
GHK-Cu: research formats
Choose the format you are researching to see route-specific notes.
Primary commercial use. GHK-Cu is highly stable in cosmetic formulations.
GHK-Cu is the most commercially significant copper peptide in cosmetics, marketed in serums and creams at concentrations typically ranging from 0.1% to 3%. It is chemically stable in peptide cosmetic vehicles and does not require reconstitution. Applied directly to skin, often under a moisturiser.
Cosmetic GHK-Cu products are standardised formulations, so no reconstitution is needed. Check the label for concentration and follow manufacturer application guidance.
Published cosmetic studies use topical application; extrapolating cosmetic outcomes to injectable GHK-Cu (or vice versa) is not supported by the existing evidence.
FAQ.
How much bacteriostatic water for a 50 mg GHK-Cu vial?
There is no single correct volume. 5 mL gives 10,000 mcg/mL, 10 mL gives 5,000 mcg/mL, and both are the same total amount of peptide. Pick the concentration that makes your intended measurement land in a readable part of the syringe, then enter it above to see the units.
Why does my GHK-Cu solution look blue?
The copper in the glycyl-L-histidyl-L-lysine copper complex absorbs in the red part of the spectrum, so the solution reads blue. Intensity tracks concentration, so a 10,000 mcg/mL solution looks noticeably deeper than a 1,000 mcg/mL one.
Is the calculator different for topical GHK-Cu?
The arithmetic is identical, it is mass divided by volume. The difference is what you read off it: topical preparation cares about percent by weight per volume, so 1,000 mg/100 mL is 1%, while injectable use cares about mcg per syringe unit.
This page is arithmetic on numbers you enter. It does not recommend an amount of GHK-Cu, and nothing here is medical advice. For what the published evidence actually supports, read the GHK-Cu profile, and for regulatory status see is GHK-Cu legal. Reviewed June 1, 2026.
Different question? The general reconstitution calculator covers every compound on the site, the blend calculator handles multi-peptide stacks, and vial longevity turns a vial into weeks of supply.
PepCue remembers your GHK-Cu vial, concentration, and draw, then tracks every dose against it. Free.