Privacy Policy

What the calculator does, and doesn't do

All three calculation modes (what is X% of an amount, what percent one number is of another, and increasing/decreasing a number by a %) are computed entirely in your browser using JavaScript. None of that is sent to our servers, because there is no server-side processing involved in producing a result. If you close the tab, the calculation session ends there, and nothing you typed persists anywhere except in your own browser's local storage, described further down this page.

Because the math runs client-side, the calculator also works the same way whether you're on a fast connection or a slow one: once the page has loaded, no further network requests are needed to get a result, and no server outage on our end can affect an answer you're already looking at.

Other pages on this site

The "How to Calculate a Percentage" and "Percentage Formula" pages are purely informational content pages: they contain no forms, collect no data, and make no additional requests to a server beyond loading the page itself. They follow exactly the same guarantees described in this policy: no personal data is collected, stored, or shared when you visit them.

If a new tool or page is added to this site in the future, it will follow the same rules described here unless this policy is explicitly updated to reflect a change, as explained in the "Changes to this policy" section below.

Local storage

To make the calculator more convenient to use, your last-entered values are saved in your browser's local storage rather than on a server, so they're still there if you reload the page. This data stays on your device: it is never transmitted anywhere, and it is never readable by any other website. You can clear it at any time using the "Clear" button on the calculator, or by clearing your browser's site data through your browser's own settings.

Cookies and tracking

This site does not set tracking cookies, does not use third-party advertising trackers, and does not build a profile of your visits over time. There is no cross-site tracking pixel embedded on any page. If your browser sends a Do Not Track or Global Privacy Control signal, there is nothing extra for it to opt you out of here, since no per-visitor tracking is happening in the first place.

Analytics

This site may use privacy-respecting, aggregate web analytics (such as Cloudflare Web Analytics) to understand overall traffic patterns, for example how many people visit a page in a given week. This kind of analytics does not use cookies and does not track individual users across sites. It never has access to the numbers you enter into the calculator, and it cannot connect a specific visit to a specific person.

Feedback form

If you use the feedback form on this site, the message you submit is sent anonymously: it does not require an email address, an account, or any personal identifier. We only see the text you choose to write. If you happen to include contact information in the message itself, that's entirely your choice; we won't ask for it.

Data security

This site is served over HTTPS, so the connection between your browser and our servers is encrypted in transit. Because the calculator's own logic never sends your input anywhere, there is no calculation data in transit to protect in the first place; the encryption mainly protects the page content itself and the anonymous feedback messages described above.

Children's privacy

This site does not knowingly collect personal information from anyone, regardless of age, since it doesn't collect personal information from any visitor in the normal course of using the calculator. The tool is appropriate for students of any age who need help with a percentage calculation for schoolwork.

International visitors

Because no personal data is collected during normal use of the calculator, there is generally nothing to process under frameworks like the EU's GDPR or the California Consumer Privacy Act for a visitor who simply uses the tool. The limited exception is the optional, anonymous feedback form described above, which by design still doesn't collect identifying information.

How this compares to calculators that require an account

Some percentage calculators ask you to sign up, save your calculation history to a server, or log in before you can use every feature. This site takes the opposite approach on purpose: everything runs anonymously and locally, so there's no account to create, no password to manage, and no calculation history stored anywhere for anyone (including us) to look back on later.

Changes to this policy

If this policy is updated, the changes will be reflected on this page with a new effective date. We recommend checking back occasionally if you have concerns about how your data is handled, particularly if new features are added to the site.

Contact

If you have any questions about this privacy policy, you can reach us via the feedback form on this site.