Rating stain products without performance claims
Stain removers are the rare category where the honest methodological answer is: there is no comparable numeric spec. Bottle volume tracks pack size, not effectiveness, so chemical stain products here are ranked by captured Amazon reviews blended with listing documentation — never by claimed cleaning power. Every page is a research summary using the supplied Amazon catalog and the primary sources linked in each guide; we have not physically tested these products.
Safety before scoring
No score can tell you a treatment is safe for your fiber, color, finish or trim. Read the garment care label and the exact product label, follow every exclusion, and spot-test a hidden area before any permitted treatment — a successful spot test never overrides a label prohibition. Never mix cleaning products.
How the comparators are built
Each comparator considers the complete eligible pool in its own lane — stain removers, laundry boosters or laundry tools — before selecting up to six distinct references. Shortlist eligibility requires a captured Amazon average and positive review count. Known pack-size or fragrance variants share one slot; this grouping does not establish identical composition or suitability. Initial order follows editorial rating, descending. Sorting by title or brand changes browsing order only. We publish no invented stain-removal percentages, review ratings or performance scores.
Formulas do not travel
A claim made for one formula never transfers to a different package variant or a sibling brand; unknown composition and compatibility stay unknown. Seller claims are attributed as claims, not independent tests.
The review-blended index
For a stain-treatment listing the automatic index is 100 × [0.45 × (Amazon average / 5) × min(review count / 50, 1) + 0.35 × min(log10(1 + review count) / log10(1 + 5000), 1) + 0.20 × documentation score / 100], rounded to a whole number. The 45% average contribution is discounted below 50 captured reviews, 35% comes from logarithmic count and 20% from the documented listing record. More feature bullets or photos can improve completeness without establishing any additional stain-removal ability. Likewise, a popular laundry booster cannot inherit evidence about a different pretreatment simply because their labels mention the same stain. Dividing the raw total by ten gives the one-decimal editorial badge. Equal results stay tied and use slug for stable order; we do not stretch the scale to appoint a winner. A catalog item without captured reviews falls back to documentation, but cannot enter the reviewed shortlist on that basis alone. The score is neither an Amazon customer rating nor a wash trial. It does not encode dose, contact time, repeated washing, colorfastness or results on your fabric: the garment and formula labels still decide whether treatment is permitted.
Images and commercial data
Guide and home scenes are labeled AI-generated editorial illustrations — not product photos or laboratory evidence. Amazon product images appear only within their supplied expiry, never more than a day after retrieval; expired ones yield to a link to the current listing. Price and stock pills use real retrieved offer snapshots and disappear after their 24-hour expiry. Discounts are not inferred; source refresh remains a separate maintenance operation.
Corrections
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