Methodology
How this site is built, where the data comes from, and what we do (and do not) check.
Where the data comes from
Every ingredient page on this site is generated from the European Commission's CosIng database — the official inventory of cosmetic substances regulated under EU Cosmetics Regulation (EC) No 1223/2009. CosIng is published as open data by the Commission's DG GROW. We import the full inventory, then re-derive each ingredient's regulatory status (banned, restricted, allowed colorant, allowed preservative, allowed UV filter, or unrestricted) from the Annex II–VI tables in the regulation itself.
Where the chemistry comes from
For each ingredient where a single small-molecule structure exists, we fetch the canonical SMILES, molecular formula, and 2-D structure from PubChem via the NCI / NIH public API, matched by CAS number. Mixtures, polymers, and plant extracts (the majority of cosmetic ingredients) do not have a single chemical structure and are presented without one. Plain-language summaries of what each ingredient does in a formulation are written from primary chemistry sources and reviewed for accuracy.
How the site is built
This is a static site. Every page — all ~547,000 of them, across 19 EU languages — is pre-rendered as plain HTML at build time using Python and Jinja2. There is no database, no JavaScript framework, no tracking, no server-side rendering. Pages load fast because there is nothing to load except HTML and CSS.
Translations
The site ships in 19 official EU languages. Major languages (German, French, Spanish, Italian, Portuguese, Dutch, Polish) were reviewed by native or near-native speakers. Other EU languages are translated machine-assisted with structural review; we mark these clearly and welcome corrections. Ingredient names (INCI nomenclature) are intentionally not translated — INCI names are the legally standardised identifiers and must remain identical across languages.
Update cadence
The CosIng database is updated by the European Commission roughly every few months as Annex amendments are published in the Official Journal. We rebuild the site whenever a new CosIng export becomes available. The "last updated" date in the footer reflects the most recent rebuild.
What we do not do
- We do not test products.
- We do not rate brands.
- We do not give medical, allergy, or compliance advice.
- We do not collect personal data — see Privacy.