How to Compare Copper Peptide Serums

The best copper peptide serum for you depends on the formula, its directions and your budget. Start with information you can check: the complete ingredient list, what any percentage measures, bottle size and current price.

About this guide: Only Child makes and sells Blue Hour Serum. This is a guide to comparing manufacturer information, not a hands-on test or an independent product ranking.

What to compare

Check Question to ask
Ingredient disclosure Does the brand publish the full ingredient list, as well as its highlighted ingredients?
Percentage Does the number describe the active ingredient in the finished formula or a supplied blend? Compare like with like.
Directions When should you apply it, how much should you use, and does the manufacturer identify combinations to avoid?
Bottle size and price What is the current price per millilitre? Include shipping when comparing the cost of an order.
Product evidence Does a performance claim refer to this finished product, an individual ingredient or customer feedback? Those are different kinds of evidence.

Products and official information

The links below lead to the manufacturers’ own product pages, checked September 9, 2026. Read each page for current ingredients, sizes, prices and directions. Formulas and availability can change.

Compare the cost fairly

Divide the price by the volume in millilitres. For example, Blue Hour’s listed $30 price for 30 ml is $1 per ml, before any shipping or tax. Compare the same currency and distinguish a temporary sale from the regular price.

Free US shipping at Only Child applies to orders over $50. Check the total at checkout when comparing a single bottle with another product.

Questions worth asking before buying

Is a higher percentage better?

A percentage alone cannot answer that. First check what it measures, then consider the complete formula and directions. Our guide to percentage claims explains the difference between an active ingredient and a blend.

Does a higher price prove a product is more effective?

Price is a cost, not evidence of a result. Look for product-specific information supporting the benefit that matters to you.

How does Blue Hour fit into a routine?

Blue Hour is an evening step after toner or essence and before moisturizer. See our application guide or contact Only Child with a product question.