Privacy Policy

This site is operated by an individual, not a company. There is no registered business entity behind it, so this policy does not reference a business registration number or a corporate address.

In data protection terms that individual is the controller: the decisions this policy describes — which tools run, what they are allowed to collect, when they are switched off — are made by one person, and that person is reachable at the contact address at the end of this page. There is no separate data protection officer; the same person answers privacy questions.

This site has no backend and no server that stores data. It is built as a static site: every page is pre-rendered, and the calculators run entirely inside your browser using JavaScript.

Because there is no server-side processing, the calculation itself is never sent to us. There is no server here to send it to, and we never see the numbers you enter.

One caveat matters, and it is easy to miss: as you type, the calculator writes your inputs into the address bar as a query string (for example, ?weight=70&height=175) so the page can be reloaded or shared with the same values. If you have agreed to the measurement tools described below, the address of the page you are on is passed to those providers, and what each one receives is not the same: Google Analytics gets it with the query string removed, while Microsoft Clarity records it as it is — so your inputs do reach Microsoft. Both sections below explain this in full.

There is no sign-up, login, or payment feature on this site, and none is planned. We do not ask for your name, email address, or any other personal information, and there is no database of users or submissions anywhere in this project.

That covers what we collect ourselves. It does not cover the third-party tools described below. If you agree to measurement, Google Analytics and Microsoft Clarity collect information about your visit — your approximate location derived from your IP address, your device and browser, which pages you open, and how you interact with them. That data is held by those companies, not by us.

Every calculator offers a button that copies a link to your result, and the share buttons copy the same thing. That link is simply the page address as it stands, which already carries the values you entered in its query string (for example, ?weight=70&height=175), so whoever opens it sees the same calculation. (The Copy result button next to it copies the result as text, not a link.)

This means that if you share that link — by message, email, or posting it publicly — the input values travel with it. Anyone with the link, and potentially anyone who can see where it was posted, can see those values. Avoid sharing a result link if your inputs are sensitive.

Nothing is measured until you say yes. On your first visit, a banner asks whether you agree to the analytics and session replay tools described below. Until you answer, neither tool is loaded: no script from Google or Microsoft runs on the page, and none of their cookies is set. If you decline, that stays true permanently.

Declining costs you nothing. Every calculator, every language, and every page behaves identically either way. The banner presents agreeing and declining with equal weight, it appears in all five languages, and it does not come back to ask again once you have answered.

Your decision is stored in your browser's local storage so the banner does not have to ask on every page. You can change it whenever you like through the cookie settings link in the site footer, which brings the banner back. Withdrawing consent stops the tools from loading on your next page view. Clearing your browser storage for this site also clears the decision, and you will be asked again.

If you agree, this site loads Google Analytics 4, which counts visits and reports them in aggregate: how many people came, which calculators they opened, roughly what part of the world they were in, what device and browser they used, and where they arrived from — a search engine, a link on another site, or a direct visit.

The purpose is narrow. Knowing which calculators are actually used tells us which ones deserve more work, and knowing which languages get traffic tells us where the site is worth expanding. We do not use it to build a profile of you, and we have no way to identify you from it.

The page address sent to Google Analytics is stripped of its query string before it leaves your browser, so the values you typed into a calculator are not part of what Google Analytics receives. Google handles the data it collects under its own privacy policy: https://policies.google.com/privacy

None of this happens before you agree. Until then the Google Analytics script is not present on the page at all.

If you agree, this site also loads Microsoft Clarity, which records your visit so it can be played back afterwards like a video. Your mouse movements, clicks and taps, scrolling, and the pages you move between are captured, along with the content of the page as you saw it.

Clarity masks the contents of input boxes in every one of its masking modes, and that cannot be switched off, so the characters you type into a calculator field are never recorded as text in the replay. The same applies to dropdowns. Its default mode additionally treats numbers and email addresses anywhere on the page as sensitive and masks them, which means the calculated figure on screen is masked too.

The address bar is where that protection ends, and this part is not hypothetical. This site writes your inputs into the page URL; Clarity records the page URL as it is; and masking URL parameters is not a setting you can flip — it requires a request to Clarity support, which we have not made. So if you agree and then use a calculator, a URL such as ?annualSalary=47600000 goes to Microsoft along with the recording. If you would rather that did not happen, decline in the banner — the calculators work exactly the same either way.

Why record at all: a visit count tells us a page was opened, but not that someone tried to enter a value, could not, and left. Replays and heatmaps show where people get stuck, which on a site where almost nobody writes in to report a problem is the only practical way to find a confusing label or an input that does not work.

Like Google Analytics, Clarity is not loaded until you agree. Microsoft handles the recorded data under its privacy statement: https://privacy.microsoft.com/privacystatement

This is the complete list of what this site stores in your browser. The Google and Microsoft entries appear only if you agree to measurement.

Clarity's third-party cookies are set on Microsoft domains rather than on this one, and one of them, MUID, is a cookie Microsoft itself describes as serving advertising among other purposes. We run no advertising through Clarity and get nothing from that cookie, but it belongs to Microsoft and we cannot narrow what it is used for — which is worth knowing before you agree. If you decline, or have not answered the banner yet, none of the entries below except the first two exist at all, and you can delete any of them at any time in your browser settings.

• NEXT_LOCALE (this site, first-party cookie) — remembers which of the five languages you last chose so you do not have to reselect it on every visit. It does not identify you and is not used for tracking or advertising.
• The consent decision (this site, kept in local storage rather than a cookie) — records whether you agreed to or declined measurement, and nothing else: the stored value is the single word granted or denied. Storing it does not itself require consent, and the reason is narrower than "the site needs it to work": the calculators run perfectly well without it. It exists to remember the privacy choice you made — above all a refusal, which we could not honour without a record of it — so that the banner does not have to ask again on every page.
• _ga (Google Analytics, first-party) — distinguishes one visitor from another so visits can be counted. Google documents its lifespan as two years.
• _ga_<container-id> (Google Analytics, first-party) — keeps session state for this specific property. Google documents its lifespan as two years.
• _clck (Microsoft Clarity, first-party) — persists the Clarity user ID and preferences for this site.
• _clsk (Microsoft Clarity, first-party) — connects several page views into a single session recording.
• CLID (Microsoft Clarity, third-party) — identifies when Clarity first saw this browser on any site that uses Clarity.
• MUID (Microsoft, third-party) — identifies a browser across Microsoft sites. Microsoft states that it is used for advertising, site analytics, and other operational purposes.
• ANONCHK (Microsoft, third-party) — indicates whether MUID is transferred to ANID, an advertising cookie. Microsoft states that Clarity does not use ANID, so this is always set to 0.
• MR (Microsoft, third-party) — indicates whether MUID should be refreshed.
• SM (Microsoft, third-party) — synchronizes MUID across Microsoft domains.
• Advertising cookies (Google, only once ads are actually served) — described in the next section.

This site may show advertisements served by Google AdSense. When ads are shown, Google and its advertising partners may use cookies and similar technologies to serve ads and measure their performance.

Google, as a third-party vendor, uses cookies to serve ads based on your prior visits to this and other websites. You can opt out of personalized advertising by visiting Google Ads Settings (https://www.google.com/settings/ads). You can also opt out of some third-party vendors' use of cookies for personalized advertising by visiting aboutads.info (https://www.aboutads.info/choices/).

The banner described above covers analytics and session replay only. Advertising consent is handled separately.

If this site serves personalized advertising to visitors in the European Economic Area, the United Kingdom, or other jurisdictions that require prior consent, that consent is obtained through a Google-certified consent management platform before any personalized ad or related cookie is set. Google requires such a platform of publishers serving ads to those visitors. It is a separate prompt from the analytics banner, and this policy will describe it in detail once AdSense is approved and it is in place.

We have nothing of our own to retain. There is no server, no database, and no log of your visit on our side, so there is no user data for us to keep or delete.

The measurement providers do retain data. Microsoft documents Clarity's retention as 30 days for session recordings — except for recordings that have been favorited and a randomly selected sample of recordings, which are kept for up to nine months — and up to nine months for heatmap data. Google retains what Google Analytics collects under its own policy: https://policies.google.com/privacy

NEXT_LOCALE and the stored consent decision remain in your browser until they expire or you clear them, according to your browser's own settings. Deleting them is entirely under your control.

The sections above describe each tool in prose. This one restates the same processing in the form European data protection law asks for, so that you can hold it against your rights: what is processed, for what purpose, on what legal basis, who receives it, how long it is kept, and whether it leaves the European Economic Area.

Where the legal basis is consent, you gave it in the banner and can withdraw it at any time. Where it is legitimate interest, no measurement is involved and nothing is passed to anyone else.

• Google Analytics 4 — Purpose: counting visits, and seeing which calculators and which languages are actually used. Data: the page address with its query string removed, the approximate location derived from your IP address, device, browser, where you arrived from, and the _ga cookies listed above. Legal basis: your consent (GDPR Article 6(1)(a)). Recipient: Google. Retention: set by Google under its own policy; we do not control it and will not paraphrase it here — see https://policies.google.com/privacy. Transfer outside the EEA: possible, see the next section.
• Microsoft Clarity — Purpose: finding where visitors get stuck, through session recordings and heatmaps. Data: mouse movement, clicks and taps, scrolling, the page as rendered with input fields masked, and the full page address including its query string. Legal basis: your consent (GDPR Article 6(1)(a)). Recipient: Microsoft. Retention: 30 days for session recordings, except favorited recordings and a randomly selected sample, which are kept for up to nine months; heatmap data for up to nine months. Transfer outside the EEA: possible, see the next section.
• Google AdSense — Purpose: showing advertising, which is how the site would pay for itself. Status: no advertisement is served here at present. The AdSense application is still awaiting approval, and the only part of this that is live is the AdSense script Google needs in order to review the site. Legal basis once ads do run: for visitors in the EEA and the UK, consent (GDPR Article 6(1)(a)) collected through a Google-certified consent management platform before any personalized ad or related cookie is set. Recipient: Google and its advertising partners. Retention and transfers: governed by Google policy, https://policies.google.com/privacy. This describes the plan, not something already in operation.
• This site itself — Purpose: remembering the language you picked (the NEXT_LOCALE cookie) and the answer you gave the banner (local storage). Data: a language code, and the single word granted or denied. Legal basis: both are stored in order to deliver the site as you explicitly asked for it, which the ePrivacy Directive exempts from prior consent; so far as personal data is touched at all, our legitimate interest under GDPR Article 6(1)(f). Recipient: nobody — the values stay in your browser and there is no server for them to go to. Retention: until they expire or you clear them. No transfer anywhere.

Google and Microsoft are companies based in the United States. If you agree to measurement, the data those tools collect can be processed on servers outside the European Economic Area, including in the United States, by each company itself and by the group companies and subcontractors it uses.

On what terms that transfer happens is decided by those companies, not by this site. What runs here is one individual using their standard free products; we sign no separate transfer agreement with either of them, and we are not going to name a transfer mechanism we have not verified — a wrong legal citation would be worse than none. What we can tell you honestly is where the terms that do apply are published: Google at https://policies.google.com/privacy, Microsoft at https://privacy.microsoft.com/privacystatement.

If that uncertainty weighs on you, the remedy is entirely in your hands: decline in the banner, or withdraw an earlier consent through the cookie settings link in the site footer. Neither tool is then loaded, nothing goes to either company, and the calculators behave exactly as they did before.

If you are in the European Economic Area or the United Kingdom, the GDPR gives you rights over personal data concerning you: access — confirmation of whether it is processed, and a copy of it; rectification of inaccurate data; erasure; restriction of processing; portability, meaning a machine-readable copy you can take elsewhere; and objection to processing carried out on the basis of legitimate interest.

Under South Korea's Personal Information Protection Act and comparable privacy laws, individuals have the right to access, correct, or delete their personal information, or to request that its processing be suspended. Because this site runs no system of its own that stores personal information, there is usually nothing on our side to access or delete.

You can withdraw your consent at any time, and it costs one click: the cookie settings link in the site footer brings the banner back, and choosing to decline stops both tools from loading, tells them to clear the cookies they had already set, and reloads the page so that nothing left running keeps collecting. Withdrawing does not make the earlier processing unlawful — what was collected while your consent was in force was collected lawfully — but it ends collection from that point on.

For data held by Google or Microsoft, there are practical routes. You can withdraw consent through the cookie settings link in the site footer, which stops both tools from loading. You can delete the cookies listed above in your browser settings, or block them there in the first place. You can disable Google Analytics on every site you visit with Google's opt-out browser add-on (https://tools.google.com/dlpage/gaoptout). And you can address access or deletion requests to the company that actually holds the data — Google (https://policies.google.com/privacy) or Microsoft (https://privacy.microsoft.com/privacystatement).

You also have the right to complain to a data protection supervisory authority. In the EEA that is the authority of the country where you live or work, or where you think the problem occurred; in the United Kingdom it is the Information Commissioner's Office; in South Korea it is the Personal Information Protection Commission. You do not have to raise the matter with us first, though we would rather you did, because most of what can go wrong here is something we can fix ourselves.

One limit is worth stating plainly instead of glossing over it: Clarity offers no way to delete one visitor. Microsoft documents deleting the entire project as the way to delete user data, which would erase every recording from every visitor at once. What we can do straight away is stop further recording — withdraw consent and nothing more is captured — and existing recordings expire on the schedule described above. If you want data about you gone sooner than that, write to us and we will consider deleting the project, because that is the only mechanism that exists.

If you believe this site holds information about you, or have any privacy question, contact us using the details below.

This site is not directed at children. The calculators, the writing around them, and any advertising the site carries are aimed at a general adult audience.

We do not knowingly collect information from children, because we operate no system that collects personal information from anyone. That reasoning no longer covers everything, though: the measurement tools above run for any visitor who agrees to them, and they cannot tell a child from an adult. This is part of why they stay switched off until someone actively agrees — a visitor who never answers the banner is never measured.

If you believe a child has used this site and you want the associated data removed, contact us using the details below. For Google Analytics we will help direct the request to Google, who holds the data. For Clarity, as explained under Your rights, no per-visitor deletion exists — deleting the whole project is the only mechanism, and we will treat such a request seriously.

This policy is rewritten whenever what the site actually does changes. The August 12, 2026 revision added the consent, Google Analytics, and Microsoft Clarity sections and corrected the earlier claim that nothing was collected at all — measurement had been added to the site, and that sentence had stopped being true. The August 13, 2026 revision named the controller, set out the legal basis, recipients, retention, and transfers for each processing, restated your rights in GDPR terms, and corrected the claim that the stored consent decision was strictly necessary for the site to work — it is necessary to remember your privacy choice, which is a narrower and more accurate reason. The date at the top of this page reflects the most recent update.