Dupes for 4D Hyaluronic Acid Barrier Essence Toner

A dupe is always the same kind of product — a serum is only compared with serums. Within that, two things are scored and blended.

Ingredient Match compares the two ingredient lists. Lists are ordered by concentration, so an ingredient near the top counts for more than one near the bottom; a dupe has to cover what matters most in the original. It weighs most of all.

Attribute Match compares what the two products are for: the benefits their ingredients are known for, such as hydrating or acne fighting. Those benefits come from the ingredients, not from tests of either product.

Only products scoring 60% or more are listed, at most 50. A match is about the formula on the label: it can't see concentrations the label doesn't print, texture, or how a product feels on your skin.