How the CuCu score works
One product, one honest number. Here’s exactly how CuCu turns an ingredient list into a 0–100 score — and where every flag comes from.
What the 0–100 score means
The score summarizes the entire ingredient list. A high score means few or no ingredients with documented concerns. A lower score means the product contains more ingredients that public scientific sources have flagged.
The score reflects the ingredients, not the brand, the price, or the marketing. Two products with identical ingredient lists get identical scores.
The five score bands
Lower score ≠ dangerous. A lower score means more flagged ingredients were found — it’s a conservative, informational signal, not a medical judgment about you or the product.
How ingredient concerns affect the score
Every product starts at 100. Each flagged ingredient reduces the score based on how strong the documented concern is.
Stronger concerns weigh more
Ingredients with high-level documented concerns reduce the score the most; moderate and limited-evidence concerns reduce it less. Ingredients prohibited by regulators can bring a score to zero.
Repeats count less
If several ingredients share the same kind of concern, each additional one counts a bit less — so the score reflects the overall picture instead of punishing one theme repeatedly.
Conservative by design
When evidence is uncertain, CuCu leans toward caution and shows a data-quality indicator, so you always know how complete the evidence behind a score is.
Types of ingredient flags
CuCu looks for ingredients that public sources have linked to these categories of concern:
Allergens
Ingredients that commonly trigger allergic reactions, including declared fragrance allergens.
Irritants
Ingredients documented to irritate skin or eyes, especially relevant for sensitive skin types.
Endocrine-disruption concerns
Ingredients under scientific or regulatory review for possible hormone-related effects.
Carcinogenicity concerns
Ingredients classified by bodies such as IARC in carcinogenicity categories based on published evidence.
Regulatory restrictions
Ingredients restricted, limited in concentration, or banned in major markets like the EU, US, or Canada.
Profile-specific cautions
Extra flags for your own profile — like pore-clogging ingredients or ingredients that may need caution during pregnancy.
Sources and references
CuCu’s flags are built on publicly available scientific and regulatory references — the same ones professionals use.
FDA
U.S. Food & Drug Administration cosmetic guidance and warnings.
Health Canada
Cosmetic Ingredient Hotlist of prohibited and restricted ingredients.
EU / SCCS
EU Cosmetics Regulation and the Scientific Committee on Consumer Safety.
CIR
Cosmetic Ingredient Review expert panel safety assessments.
IARC
International Agency for Research on Cancer classifications.
ECHA
European Chemicals Agency — REACH and substances of very high concern.
IFRA
Fragrance ingredient standards, where relevant to a product.
Open data
Public product databases such as Open Beauty Facts for product identification.
Important disclaimer
CuCu scores are informational and conservative. They are not medical advice, diagnosis, or a guarantee that a product is safe or unsafe for every person. Ingredient science evolves, formulations change, and individual skin reacts differently. Always read the product label and consult a qualified professional for medical or skin-health concerns.