Cookie Policy

Last updated: 4 August 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 two optional analytics tools that load only if you choose to accept them.

Optional analytics — Microsoft Clarity

If you consent to analytics through the InMobi Choice consent message, 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 consent. You can withdraw consent using the Cookie preferences link in the footer, which reopens the consent message. For more, see Microsoft's Privacy Statement.

Optional analytics — Google Analytics 4

The same consent also loads Google Analytics 4, which tells us which calculators are used, how visitors arrive at them, and where pages perform badly. It sets these cookies:

• _ga — distinguishes one browser from another so visits group into sessions. Expires after about two years.
• _ga_<container-id> — keeps the state of the current session. Expires after about two years.

We run Analytics for measurement only: we do not enable Google Signals, advertising features, or remarketing audiences, so your visit is not used to target ads to you, and the numbers you type into calculators are never sent to Google. The Analytics tag is not loaded, and none of these cookies are set, unless you consent — withdraw it at any time with the Cookie preferences link in the footer. For more, see Google's Privacy Policy and how Google uses data from sites that use its services.

Consent management — InMobi Choice

Your advertising and analytics consent choices are collected by InMobi Choice, a certified consent management platform, and recorded in cookies on this site: euconsent-v2 (your IAB Transparency & Consent Framework choices), IABGPP_HDR_GppString (US state privacy signals) and usprivacy, each kept for up to 13 months. These let advertising partners read and honour your choices. See InMobi's Privacy Policy.

Strictly necessary local storage

The Site uses browser localStorage (not cookies) for a few small, functional purposes:

• bml-theme — your chosen theme (light or dark). If the key is absent, your operating-system preference is used.

• bml-locale — the region whose calculators you last chose (UK, US, Australia or Canada), so links point at the right version.

• bml-project — your My Project take-off. When you press Save to My Project on a calculator, the tool, the inputs and the result you chose to save are kept here so you can review or print them together on the My Project page. It holds only what you explicitly save — no account, no identifiers, no tracking — and never leaves your device. Remove individual items or clear the whole list at any time from that page.

These stay on your device and are never sent to us. Calculator inputs are not stored automatically — refreshing the page resets them; only the estimates you deliberately save to My Project persist.

Anonymous usage logging (no cookies)

Separately, we record an anonymous, cookieless event when a calculator is used: which tool it was, the name of the figure it produced, your approximate province/region and device type (from network request headers). The values you type and the results calculated from them are not transmitted or stored. 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

Apart from the two consent-gated analytics tools described above, there are no tracking or advertising tags on this site — no Facebook Pixel, no ad network pixels, no cross-site profiling. 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 localStorage entry, and any Microsoft Clarity or Google Analytics cookies, at any time via your browser's site-data settings.