Privacy Policy

What we collect, what we don't, and the third parties involved.

Effective: September 30, 2026 · Last updated: September 30, 2026

Current status: the site loads a self-hosted, cookieless analytics script (Plausible) and no advertising scripts. Valid calculator inputs are automatically saved in this browser so the current project can survive a refresh. When you deliberately create a share link, the project inputs are placed in that link. This policy will be updated before any new analytics or advertising service is activated.

What we do not collect

The calculators run entirely in your browser. The dimensions, density, and prices you enter are used to compute your result on your device. The site code does not submit those project fields to an application server, but normal hosting logs and third-party image requests are separate from the calculator's project storage. Automatic browser saving and share-link behavior are explained below. We never ask for your address, and the only active analytics is the aggregate, cookieless measurement described below.

Analytics

Plausible Analytics is active, served from our self-hosted installation at analytics.lingyi.systems. It is a cookieless, aggregate page-view measurement: no cookies or persistent identifiers are set, and it additionally counts outbound-link clicks, file downloads and form submissions as totals — not the content of what you clicked, downloaded or submitted. It does not receive the dimensions, prices, area names or other project values you enter.

Saved and shared calculator projects

The main calculator automatically saves valid current inputs in your browser's local storage so they are available after a refresh. ChoosingSave project can also keep up to five named recent projects, and scenario comparison stores a baseline in the same browser. Those records remain until you delete them or clear this site's browser storage. If browser settings block storage, calculations still work but the site cannot persist those records. When you choose Share project, the measurements and calculation assumptions are encoded—not encrypted—into the URL fragment you copy; anyone who receives that link can read those project inputs. Older share links may use a URL query parameter, which can be visible to the web server when the link is opened. Do not put addresses, customer names, quote documents, or other sensitive information in area names.

Hosting and external images

Like most websites, the hosting provider may process ordinary request data such as an IP address, requested URL, timestamp and browser information for delivery, security and operational logs. The provider's exact retention configuration is not stated here because it has not been independently verified for this site. The homepage also loads directory-badge images from their providers; those image hosts may receive normal request metadata. The calculator does not intentionally include project dimensions, prices or area names in those image requests.

Advertising (Google AdSense)

Google AdSense is not active as of the date above. If it is activated, Google and its advertising partners may use cookies, web beacons, IP addresses, and other identifiers to deliver, measure, personalize, and limit ads. Google's use of advertising cookies can allow Google and its partners to serve ads based on visits to this and other websites.

You can review or opt out of personalized advertising in Google Ads Settings. See How Google uses information from sites or apps that use its services and Google's list of certified third-party ad technology providers. When consent or an equivalent choice is legally required — including for visitors in the EEA, United Kingdom, or Switzerland — a Google-certified consent management platform will be configured before Google advertising or related data processing is activated for those visitors.

Cookies

The current calculator uses browser local storage for saved projects; local storage is not an advertising cookie. If advertising or analytics is later enabled, first- or third-party cookies may also be used for preferences, security, measurement, frequency capping, and ad delivery. You can control cookies through your browser settings and, where available, the site's consent controls.

Data retention and your choices

We do not receive calculator projects saved only in your browser. You can remove those records by deleting saved projects in the calculator or clearing this site's browser storage. Shared project URLs remain wherever you or a recipient saved or posted them, so treat those links as readable project records and avoid including personal information.

Changes

We will update this page as our analytics and advertising setup changes. Material changes will be reflected here with a revised date.