Your measurements stay in the page.
The calculation runs in your browser. The calculator does not send your dimensions, swatch weight, skein label or result to a server.
No account, no measurement storage
We do not provide accounts, upload forms or cloud storage. The calculator does not write measurements to cookies, local storage or a database. Refreshing the page clears the measurements. Your browser may offer its own form-restoration behavior; that is controlled by the browser.
Worksheets are local downloads
“Save worksheet” creates a text file locally in your browser. It contains the inputs, result, date and assumptions. The site does not receive a copy. Printing uses your browser's print dialog; any printer or PDF service you choose has its own handling rules.
What happens when you visit
Your browser requests the page and its own CSS and JavaScript files from the hosting provider, Cloudflare. Like ordinary website delivery, those requests expose connection information such as IP address and request metadata to the provider. This is different from sending calculator inputs. Cloudflare's applicable hosting and security practices govern its handling of those requests.
The site does not add analytics scripts, ad scripts, external fonts, tracking pixels or third-party embeds. Its Content Security Policy blocks script-initiated network connections with connect-src 'none'. This does not prevent normal page navigation or the host from serving and logging web requests.
External reference links
The guide links to the Craft Yarn Council for background reading. Following those links leaves this website and subjects you to that website's policies. We do not load those pages in the background.
Changes
If tracking, accounts, uploads or monetization are introduced, this page and the implementation must be updated together before release. Current version: October 9, 2026.