Dupes for The Inkey List 10% Niacinamide Serum Duo.

Hero actives first. We compare the meaningful actives named on the original’s label. Ubiquitous bases — water, glycerin, hyaluronic acid, butylene glycol — are never treated as evidence that two formulas do the same job.

Then the rest of the list. How many of the original’s ingredients also appear on the other label, always shown as a count against the original’s own length — never a headline number on its own. Candidates share at least three label ingredients with the original, common bases are down-weighted, and meaningful actives count more.

Price. Savings compare the best real offer we hold for each product, or its catalog price when there is no offer, and only within one currency. Commissions never affect the order of this list.

Your profile. Signed in, rows also mark ingredients you told us to avoid and the goals you set. That changes what is highlighted and what is ranked first — never which products qualify, and never what anyone else sees.

method v2 · 2026-08-30 — tiers replace the single 50%-share floor; same-brand aliases collapsed; hero actives exclude commodity humectants; sunscreens are never called dupes; labels under 10 ingredients are never called dupe sources.