Privacy Policy

CalcLab (the "site") takes your privacy seriously and complies with applicable privacy laws. This policy explains what information the site handles and how.

1. Calculator inputs, saved text and result links

The calculation code runs in your browser and does not send your inputs to a server to calculate a result. Typing does not automatically create a result-sharing URL. Saved text and access by external scripts are described below.

Text storage in the Korean character counter is opt-in. Enabling it in the Korean character counter saves the current text and later edits in this browser's localStorage. Saving starts off on each visit, and earlier text is not restored automatically. The load button replaces the editor with the saved text. Turning saving off or clearing the editor keeps the saved text; use the delete-saved-text button to remove it. Browser settings can prevent saving, and the browser can clear stored data. Other people using the same browser can load the saved text.

"Copy result link" lets you share the inputs used for a calculator result. That button places them after the hash mark (#), for example …/en-us/baby-percentile/#h=75.5&w=9.4. This part of a URL is called a fragment and is not included in the HTTP request made when you open the link (RFC 3986 §3.5).

The person receiving the link can see those inputs. Check the values and the recipient before sharing a salary, a child's measurements or other sensitive information.

After reading a result link into the input fields, the page removes the values from the address bar to reduce exposure when sharing or copying the address. Clearing the address bar does not block access by external scripts on the page. Third-party advertising or analytics scripts running in the same document can access input fields and this site's browser storage. This describes what those scripts can access; it is not a finding that inputs have actually been collected or transmitted.

Some links created on or before 16 August 2026 contain values after a question mark, such as ?h=75.5. Opening these older links can include the values in the initial HTTP request. Clearing the address after reading it does not undo a request already sent. Use "Copy result link" to make a new sharing link.

2. Accounts and personal information

The site has no sign-up feature. We do not directly collect personal information such as your name, email address, or phone number.

3. Access logs

The hosting provider this site uses may keep standard server logs (including IP address, access time, and browser information) as part of normal service operation and security. This information is used only for aggregate statistics and troubleshooting.

4. External price and exchange-rate data

Metal prices and exchange rates are fetched in advance, at the moment the pages are built, and written straight into the page. The site is rebuilt once a day and the figures are refreshed then. That means your browser does not contact any external price server when you open a page, and your IP address is never passed on to a data provider. The reference time shown next to a figure is the moment that figure was fetched, not the moment you loaded the page. Where you would rather work from a number you have checked yourself, the gold calculator takes a dealer's price typed in by hand.

5. Cookies and advertising

The site may display ads (for example, Google AdSense) to support its operation. Third-party ad vendors, including Google, may use cookies to show ads based on your prior visits. Information processed by ad vendors may include the page address. Section 1 describes how scripts can access input fields and browser storage. If you prefer not to see personalized ads, you can opt out in Google Ads Settings.

6. Visitor statistics

To see which calculators actually get used, the site runs Cloudflare Web Analytics. On pages that include the measurement script, it reports to Cloudflare when the page loads. What Cloudflare records is the domain and path of the page, the page you arrived from (the referrer), your browser, operating system and device type, the country you are in, and page load timings. Cloudflare states that the product uses no client-side state such as cookies or localStorage and does not identify individual visitors or follow them from one site to another, and that it does not log query strings, precisely so that potentially sensitive values sitting in an address are not collected. The details are in the Cloudflare Web Analytics documentation.

7. Changes to this policy

If anything in this policy is added, removed, or changed, we will announce it on this page.

8. Contact

Questions about privacy: calculab.admin@gmail.com

Effective date: September 16, 2026