The reference
index of paper.
Every paper grade, mill, brand and certification, catalogued, cross-referenced and assigned a permanent WPI ID. Free, open, and obsessively maintained by people who love a good watermark.
A specialty grade, 18 to 35 gsm, indexed with a permanent WPI ID and cross-referenced to the mills that run it. Open the entry for the full specimen sheet, fibre detail, and production sources.
A sample
of the index.
Each entry is a permanent record, cross-referenced with the mills that produce it, the brands that sell it under a trade name, and the use-cases it serves. Click any row to open the full specimen sheet.
20 certifications, tracked.
Chain-of-custody, food contact, ecolabels, and packaging safety schemes. Every certification page lists every mill we have on record as currently holding it.
One sheet,
five questions.
What is the fibre? How is it held together? What is on its surface? How flat is it made? And how white is white? Every entry in the index answers those five questions, the same way, in the same order, every time.
That is why a WPI ID is useful: it pins one specific answer-set to one specific grade, forever. Mills change, brand names shift, but WPI-g-000901 is always the same indexed record.
Open the glossary →Observe.
Trade catalogues, mill datasheets, ISO standards, customs codes. We read the boring stuff so you don't have to.
Normalize.
We reconcile a thousand trade names into one canonical grade with a single spec sheet and a permanent ID.
Cross-reference.
Every grade links to its mills, brands, certifications, and articles. Every mill links to every grade it runs.
Publish.
Free, open, CC-BY. No paywall, no login, no hidden “pro” tier.