SIMPLE TOOLS. CLEAR INFORMATION.

Privacy & analytics.

Updated August 28, 2026.

Calculator inputs

Calculations run locally in your browser. The calculator code does not send measurements to a calculation server, create accounts, or save inputs in a database. The production site also uses the analytics services described below. Refreshing the page resets values unless you followed a link carrying an area in its URL fragment.

Moving between calculators

A link to the next calculator can include measurements after the # symbol in the URL. That fragment is read by the receiving page in your browser and is not part of the HTTP request sent to the hosting server. Anyone you share that full URL with can read those measurements.

Google Analytics

The production website uses Google Analytics 4 to understand visits and site usage. The Google tag loads from Google and may use cookies to collect page views, referral information, browser and device information, and interaction events according to the Analytics property settings. Analytics tags are not included in local development or preview deployments.

Our Google Analytics configuration removes URL fragments from the page address and referrer sent to Google, so measurements carried between calculators are not included in those fields. We do not add calculator inputs or results to custom analytics events. Page addresses can still include query parameters; do not put personal information in shared URLs.

See Google’s Privacy Policy and Google’s Analytics opt-out browser add-on.

Microsoft Clarity

We use Microsoft Clarity on the production website to understand clicks, scrolling, and navigation through heatmaps and session replays, and to improve the calculators’ usability. Clarity collects page and interaction information and may use first-party and third-party cookies and other tracking technologies. Microsoft processes this information under the Microsoft Privacy Statement.

We mark the calculator section for Clarity content masking, including its inputs and displayed results. This masks content in recordings, but does not prevent collection of interaction metadata or page URLs. Unlike our Google Analytics page-address configuration, this Clarity installation does not strip URL fragments; measurements in links may therefore be included in recorded URLs. Do not enter personal or sensitive information in shared links.

Cookies and browser storage

Browser privacy settings and extensions can restrict cookies or block analytics requests. The calculator works without these analytics services. The calculator itself does not use localStorage or sessionStorage, but analytics services may use browser storage. Fonts are served with the site rather than requested from an external font service.

Hosting and external links

Vercel hosts this website. Serving pages can involve standard request information such as IP address, browser information, and requested path. Hosting logs and infrastructure practices are governed by the hosting provider. External sources linked from the site have their own privacy practices.

Copy and print

“Copy result” writes the calculation summary to your clipboard only when you select it. “Print” opens your browser’s print dialog. Neither action uploads your result to this site.

Changes to the site

This notice will be updated when the site’s data practices change, including changes to analytics or the addition of ads, accounts, or other data collection.