Privacy Policy

What we collect

Calculator inputs: nothing. Every calculation on thecalclibrary.com runs entirely in your browser using JavaScript. The numbers you type: your income, weight, blood pressure, product costs — are never transmitted to our servers, because there is no server-side calculation to transmit them to. They are not logged, not stored, and not shared with advertisers.

Site preferences. Your light or dark theme choice is stored in your browser's local storage so the site remembers it next visit. It stays on your device.

Standard server logs. Our hosting provider records basic request information: IP address, browser type, referring page, and the time of the request, to keep the site running and detect abuse. These logs are retained for a limited period and are not linked to you as an individual.

Analytics

We use Google Analytics 4 to understand which calculators are used and how people find the site. It records pages visited, approximate geographic region, device and browser type, and the referring site. It does not receive anything you type into a calculator. IP addresses are anonymised by default in Google Analytics 4.

Advertising

This site is free to use and is funded by display advertising, which we intend to serve through Google AdSense. The following applies to that advertising:

• Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this site or other sites.
• Google's use of advertising cookies enables it and its partners to serve ads to you based on your visits to this and other sites on the internet.
• You may opt out of personalised advertising by visiting Google Ads Settings.
• You can opt out of third-party vendors' use of cookies for personalised advertising at aboutads.info/choices or, in Europe, at youronlinechoices.eu.
• Advertising has no influence on the content of any calculator. There are no sponsored calculators, paid placements or affiliate links inside the tools, see our editorial policy.

Cookies

Cookies used on this site fall into three groups. Strictly necessary cookies keep the site working and store your theme preference. Analytics cookies, set by Google Analytics, measure how the site is used. Advertising cookies, set by Google and its partners, are used to select and measure ads.

You can block or delete any of these through your browser settings, and every calculator on the site will continue to work, the calculations happen locally and do not depend on cookies.

If you are in the EEA, UK or Switzerland

Where required, a consent banner will ask permission before any analytics or advertising cookie is set, and you can withdraw or change that choice at any time. Refusing consent does not restrict access to any calculator.

Third-party services

The site is hosted on Vercel, which processes requests to serve pages and keeps its own server logs under its privacy policy. Fonts are served from our own domain rather than a third-party CDN, so no request data is shared for fonts. Analytics and advertising are provided by Google and handled under Google's policy for partner sites.

Children

This site is not directed at children under 13 and we do not knowingly collect personal information from them. Advertising served on the site is not personalised to children.

Your rights

Because we do not build user profiles or store personal data tied to you, there is generally nothing for us to access, correct or delete. If you have contacted us by email you can ask us to delete that correspondence at any time. Depending on where you live you may have rights under the GDPR, UK GDPR, or CCPA, write to us and we will honour them.

For data held by Google through analytics and advertising, use the Google links above, which reach Google directly.

Changes to this policy

If this policy changes materially, the updated date at the top of the page will change and the substance of the change will be described here.

Contact

Questions about privacy can go to our contact page or directly to hello@thecalclibrary.com.