Privacy Policy
This page explains, in plain terms, what happens to your data when you use the weight calculator, the IBW formula page, or the height and weight chart on this site. The short version: this site makes zero external network requests of any kind for its calculations. Your height, weight and gender never leave your browser, because every IBW formula, average and healthy-weight range is computed entirely with local JavaScript running on your own device.
What the calculator does, and doesn't, send anywhere
Every calculation on this site, the four IBW formulas, their average, the WHO healthy-BMI weight range, and the below/within/above comparison against your current weight, runs entirely in your browser using JavaScript. None of it is sent to our servers, because there is no server-side processing involved in producing a result at all. This tool needs nothing from the outside world to compute its answer, so it makes no external requests whatsoever when you use it.
Local storage: your last entry, saved in your own browser
The calculator page saves your most recently entered height, weight, gender and unit preference to your browser's localStorage, a standard browser feature that keeps small pieces of data on your own device between visits, so the fields are pre-filled the next time you open the page. This data stays on your device. It is never transmitted to us or to any third party, and you can clear it at any time using the Reset button on the calculator, or by clearing your browser's site data through your browser's own settings.
Analytics
This site may use Cloudflare Web Analytics, a privacy-focused analytics service that does not use cookies and does not track individual visitors across sites. It does not build an individual profile of you, and it does not share or sell data to advertisers; it would only help us understand whether the site is working correctly and which pages are useful, not identify or target individual visitors. As of the time you are reading this, analytics is not actively configured for this domain, so the corresponding script does not load at all, and no visit data is collected by us in any form.
Cookies
This site does not set marketing or tracking cookies. Any cookie-like storage that exists is limited to the localStorage feature described above (which is not technically a cookie, and is not sent to any server on every request the way a cookie is), and your own browser's theme preference (light or dark mode), which is also stored locally and never transmitted anywhere.
Server logs
Like virtually every website, the infrastructure this site runs on (Cloudflare) keeps standard technical logs of requests, things like IP address, browser type, requested page and timestamp, for security and reliability purposes such as detecting abuse or diagnosing outages. These are operational logs at the infrastructure level, not a profile built about you; they are not used for advertising, not sold, and not cross-referenced with anything you enter into the calculator.
Health information disclaimer
This site is an informational and educational calculator, not a medical device or a substitute for professional medical advice. Nothing you enter is reviewed by us, stored on a server, or used to provide you with individualized medical guidance, because there is no server-side processing at all, as explained above. The results shown are general population-level estimates. Always talk to a doctor or a registered dietitian for advice specific to your own health.
Children's privacy
This site is a general-purpose reference and calculator tool not directed at children, and we do not knowingly collect personal information from anyone, of any age, since none of the tools on this site require you to submit personal information in the first place. There is no account system, no form that asks for a name or email, and no mechanism by which we could identify a visitor's age even if we wanted to.
Changes to this policy
If how this site handles data changes meaningfully, for example if an advertising network is added, this page will be updated to reflect that before the change takes effect, not after. Because this policy is a static page rather than something requiring an account or subscription, there's no notification list to sign up for; checking back here is the way to see the current version.
The feedback widget
If you use the thumbs up or thumbs down feedback control on a tool page, that sends an anonymous signal (which tool, and whether the feedback was positive or negative) to help us understand which tools are working well. It does not include your calculator inputs (your height, weight or gender), your IP address is not linked to the feedback in any way we can access, and there is no way for us to trace a specific piece of feedback back to a specific visitor.
Third-party links
Some pages on this site may link out to other sites for further reading (for example, a health authority's own reference material). Those sites have their own separate privacy policies and practices, which we don't control and this policy doesn't cover; we'd encourage you to review the privacy policy of any third-party site you visit from a link here.
Contact
If you have a question about this policy or how this site handles data, use the feedback control on the calculator page, or email contact@weightcalculator.xyz directly.