Stitch Math is an independent reference for knitters and crocheters. This page explains how the numbers, records and guides are made — and what they do not claim.
What this site is
Stitch Math publishes four calculators, the standard needle and yarn-weight charts, a dated library of yarn specifications, and practical guides to gauge, substitution and quantity. It is written for people making real projects, not for a search engine.
Who writes it
Pages are written and edited by the Stitch Math editorial desk. We deliberately do not invent named authors or attach qualifications the site does not have. We are not knitting teachers, yarn manufacturers or professional pattern designers. The calculators are arithmetic tools; the guides summarise published standards and practical technique. When a question needs hands-on judgement about your gauge, your yarn or your pattern, the page says so.
How the numbers are checked
Size and weight conventions follow the Craft Yarn Council industry standards. Yarn records use manufacturer and retailer listings for put-up, fibre, gauge and recommended tools. Each record carries the date it was checked, and where a line is sold in more than one put-up the standard skein is named.
Every calculator prints its formula so the arithmetic can be reproduced by hand. Results are tested against known cases, including unit conversion, rounding, rib multiples and nearest-size matching. Where sources disagree, the record says so and the label on the skein wins.
How we use AI tools
We use AI tools to help draft, structure and edit, in the same way a writer might use a spellchecker, a thesaurus or a research assistant. AI is not a source. Every published page is checked against its cited sources, generic passages are rewritten, and unsupported claims are narrowed or removed. We do not use AI to invent sources, quotes, measurements or yarn specifications. If a figure cannot be verified, it is left out rather than guessed.
Corrections and updates
Yarn records show the date they were checked; guides show a published date. When a source changes, a manufacturer reissues a yarn, or a reader reports an error, we correct the page and update the date. To report a problem, email [email protected] with the page, the sentence and a source if you have one. Corrections with a citable source are prioritised.
Independence and funding
No yarn brand or retailer has editorial input. Yarn records and guides are written for readers, not for brands. The site is funded by its own operating budget.
Artwork and photographs
Calculator and reference illustrations are original vector work made for this site. Guide photographs are openly licensed images from Wikimedia Commons, credited in the caption and listed on the photo credits page. We do not reproduce manufacturer descriptions or product photography.
The short version
Standards for sizes. Dated sources for yarn data. Formulas printed on the page. No invented authors or citations. Corrections made in public. Illustrations original; guide photographs licensed and credited.
Last updated 23 October 2026.