Methodology

Where the numbers come from

Every product's fiber content is quoted, word for word, from the maker's product page, or from a major retailer's page when the maker does not publish one. We store the quote, the page it came from, and the date we read it. We never estimate, average, or infer a fiber content, and we never use Amazon listings as the source of a number.

What counts as wool

We use the definition in the US Wool Products Labeling Act: fiber from the fleece of sheep or lamb, and the hair of the Angora or Cashmere goat, camel, alpaca, llama, and vicuña. The wool percent is the sum of those fibers. Silk, cotton, bamboo, and all synthetics are not wool. The "type" column lists which wool-family fibers are present.

What "pure wool" means

No synthetic fibers at all: no nylon, polyamide, polyester, acrylic, elastane, spandex, or lycra. 100% wool is pure. Wool with only other natural fibers, silk, cotton, linen, or hemp, is pure. Two percent elastane makes it a blend, and we say so, because that two percent is why most wool socks hold their shape and why pure ones wear differently.

How often numbers are re-checked

A script re-reads every source page on a schedule, compares the fiber statement with what we stored, and updates the "verified" date. When a statement changes, the old one is kept in the product's history and the change is listed on the changes page with its date. When a page stops stating a fiber content, the product is marked and a person looks. Pages are fetched gently: one request per second per site, honoring robots.txt, identifying ourselves as Wool Percent.

Ranking

By wool percent, highest first. Ties go to pure wool, then alphabetical. Nothing else moves a product: not price, not whether a link pays a commission, not whether a maker asks.

Corrections

If a number is wrong, tell us and point at the page. We would rather be corrected than be read.