Methodology

PerfectSkin scores products only from what owners say on Reddit. We do not use Amazon reviews, manufacturer claims or generated text as review data.

Data

We collect public Reddit threads and comments (via the Arctic Shift archive) from r/30PlusSkinCare, r/AsianBeauty, r/SkincareAddiction, r/acne, r/koreanskincare, r/tretinoin, then match comments to specific models by name and model number. 55,189 comments were scanned for this build. A comment counts toward a product score only when it names that model and the commenter describes their own use (an owner comment). Bot-like, promotional and list-style comments are excluded. Matching and classification are automated with keyword rules, so some errors are possible.

Score

• Owner sentiment (40%): a weighted Bayesian average of owner comment ratings, (C×m + Σwᵢrᵢ)/(C + Σwᵢ) with C = 5 and m the category mean, so a handful of comments cannot reach 5.0. Upvotes add weight; comments from the last 12 months count double; long comments count 1.5×.
• Recommendations (15%): 1 + 4 × log(1+n)/log(1+max) for owner comments that recommend the model.
• Spec score (25%): not rated in this build, because listings report specs inconsistently. Its weight is redistributed.
• Value (20%): price snapshot versus the category; within 10% of the cheapest scores 5, the priciest scores 1.

Components without evidence show “Not rated” and their weight is redistributed; they are never treated as zero.

Evidence thresholds

A product is published only when its Amazon listing was verified live and it has at least one owner comment. Products with fewer than 5 owner comments, brands with fewer than 3, and use-case pages with fewer than 3 qualifying models are marked noindex and left out of the sitemap. Comparisons need 5+ owner comments on both sides.

Prices and links

Prices are snapshots from the Amazon listing on the date shown. Every Amazon link was checked live on that date. PerfectSkin is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.

Independence

Commissions never affect scores, rankings or verdicts. Every product is scored by the same formula.

Last updated 2026-11-07.