Cookies & consent

Last updated: 6 October 2026.

Preferences and consent storage

We save your selected colour theme in your browser’s local storage until you change it or clear site data. Google’s Privacy & messaging consent manager uses browser storage to remember your privacy choices and whether to show its message again.

Advertising choices

For visitors in the EEA, UK and Switzerland, Google’s consent message provides options to consent, refuse consent or manage individual purposes and partners. The message lists the applicable storage durations and processing details. Optional advertising storage and personalisation require your consent where applicable. Google Analytics measures visits and calculator interactions only after analytics consent. Ad placements are currently disabled.

Analytics cookies

After analytics consent, Google Analytics uses _ga and _ga_* cookies to distinguish visits. We configure these cookies to expire after 180 days without extending their duration on each visit. Google receives technical information such as IP address and browser information, page titles, clean page addresses and tool event names. Calculator values, search terms, URL queries and fragments are excluded from our analytics events. Advertising personalisation and Google signals are disabled in our Analytics configuration.

Change your decision

Use “Analytics settings” to change your analytics choice. Your choice is stored locally for 180 days. Use “Privacy and cookie settings” in the footer of a calculator or the home page to reopen the Google message and change or withdraw your choice. On this information page, that link takes you to the home page so you can open the settings. You may also clear cookies and site data in your browser; doing so removes saved preferences and may cause the message to appear again.

If a content blocker prevents the consent manager from loading, settings may be unavailable. You can still read these pages and use the calculators. See our privacy policy for contact details and information about Google and hosting providers.