Cookie Policy

Last updated: 7 June 2026

BuildMetricLab keeps cookies to an absolute minimum. We set **no

advertising cookies and no cross-site tracking cookies**. The only

cookies on this site come from one optional analytics tool that loads

only if you choose to accept it.

Optional analytics — Microsoft Clarity

If you accept analytics in the cookie banner, we load **Microsoft

Clarity** to understand how the calculators are used, through aggregated

heatmaps and anonymised session replays. This helps us find confusing

layouts and steps that don't work well. Clarity sets two cookies:

• `_clck` — identifies a returning visitor so page views group into

one session. Expires after about a year.

• `_clsk` — links page views within a single session. Expires at the

end of the session.

Text you type into calculator fields is masked in your browser before

anything is sent, so the values you enter are not captured. Clarity does

not load — and these cookies are not set — unless you press Accept.

You can withdraw consent by clearing site data, after which the banner

reappears. For more, see

Microsoft's Privacy Statement.

Strictly necessary local storage

The Site uses browser localStorage (not cookies) for two small

preferences:

• `bml-theme` — your chosen theme (`light` or `dark`). If the key is

absent, your operating-system preference is used.

• `cookie-consent` — records your accept/reject choice so the banner

does not reappear on every visit.

Both stay on your device and are never sent to us. Calculator inputs are

not stored — refreshing the page resets them.

Anonymous usage logging (no cookies)

Separately, we record an anonymous, cookieless event when a calculator is

used: the tool, the inputs and result, your approximate country/region and

device type (from network request headers). It sets no cookie, stores

nothing on your device, and contains no information that identifies you.

Because it does not store or access information on your device, it does not

require consent.

No other tracking

There are no Google Analytics, Facebook Pixel, or advertising tags on this

site. If we add anything further that stores information on your device, we

will update this page and request consent first.

Clearing data

You can clear the `bml-theme` and `cookie-consent` localStorage entries,

and any Microsoft Clarity cookies, at any time via your browser's site-data

settings.