Clinical values you enter

Age, sex, weight, height, serum creatinine, cystatin C, urine volume and every other value you enter into a calculator on this site are processed entirely within your browser, by JavaScript running on your own device.

These values are never:

transmitted to this site’s servers or to any third party;
written to a server log or an analytics event;
stored in a database;
saved to local storage, session storage or a cookie.

Closing or refreshing the page discards them. This is a property of how the site is built rather than a policy commitment — there is no endpoint that accepts a clinical value, because the calculation code never makes a network request.

Accounts

There are none. No signup, no login, no email capture, no paywall. Every calculator on this site is fully functional without identifying yourself in any way.

Cookies

This site sets no advertising cookies and joins no advertising network. Google Analytics sets a first-party measurement cookie (_ga) containing a randomly generated identifier, used to tell a returning visit from a new one. If you switch language, a preference cookie may be set by the localisation layer purely to remember which language version to serve you; it contains a language code and nothing else. Your browser’s theme preference is kept in local storage on your own device and is never sent anywhere.

Analytics

This site uses Google Analytics 4 to count page views. It records which pages are visited, the approximate region a visit came from (derived from IP address, which Google does not expose to us), the referring site, and general device and browser information.

No analytics event on this site carries a clinical value. This is structural rather than a setting that could be changed by accident: the calculators keep every input in memory only and never write one to the page address, so the URL recorded with a page view cannot contain one, and the site sends no custom analytics events at all — only the automatic page view. Google Signals and ad personalisation are switched off, so this traffic is not joined to an advertising profile.

Google’s own handling of the data it collects is governed by the Google Privacy Policy. You can opt out of Google Analytics entirely in every site you visit by installing the Google Analytics opt-out browser add-on, or by using any browser setting or extension that blocks it. The calculators work exactly the same either way — nothing on this site is gated behind analytics.

Server logs

The hosting provider serving this site may keep standard technical request logs — IP address, timestamp, requested URL, user agent — as is normal for any web server and necessary for security and abuse prevention. Because clinical values are never sent to the server, they cannot appear in those logs.

Third parties

Google Analytics, described above, is the only third-party script this site loads. There are no embedded widgets, no social media trackers, no advertising network, no comment system and no external fonts — the typeface is self-hosted and served from this origin. Everything else on the page, including every line of calculation code, comes from this domain.

Security

The site is served exclusively over HTTPS. It sends a restrictive permissions policy disabling camera, microphone and geolocation access, sets X-Content-Type-Options: nosniff, and restricts framing.

It also sends a Content Security Policy that names every origin the page is allowed to contact. Google Analytics is the only external destination on that list, and form-action is set to none — there is no form on this site that can submit anywhere. You can read the policy yourself in the response headers; it is the reason the guarantee above is checkable rather than merely asserted.

Your rights

No clinical data is collected, so there is nothing of that kind to request access to, correct or erase — it never reaches us in the first place. The analytics data described above is pseudonymous and aggregate: it is not linked to a name, an account or an email address, and we have no way to identify which rows belong to you in order to retrieve or delete them. If you would rather not be counted at all, the opt-out linked above prevents the data being collected, which is the more effective remedy.

If you have contacted us by email, that correspondence is the only record we hold that identifies you, and you can ask for it to be deleted at any time.

Children

This site is intended for healthcare professionals and students. It is not directed at children and does not knowingly collect information from anyone.

Changes to this policy

If this policy changes, the revised version will be published on this page. Any change that weakened the client-side-only guarantee above would be a substantive change to how the site works, and would be stated prominently rather than buried here.

Contact

Questions about this policy can be sent to gemprogrammersgp@gmail.com. Please do not include patient information in any message — see the note on the contact page.

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