Privacy
Last updated 15 July 2026.
Your privacy is straightforward here, because the site is built to need almost nothing from you. In short: the figures you type never leave your browser, and the site sets no cookies.
Your figures never leave your browser
The calculator runs entirely in your browser. Your salary, pension, bonus and every other input are used only on your device to work out the result. They are never sent to a server and never logged. There is no account and no backend that sees them.
By default the figures are held only while the page is open and are gone when you close it. If you turn on the option to remember your inputs, using the button at the top of the page, they are saved in your own browser so they are ready for you next time. They are still never sent anywhere, and turning the button off deletes them straight away.
Analytics
We use Vercel Web Analytics and Speed Insights to understand aggregate traffic and page performance. Both are privacy-preserving and cookieless, served from this site's own domain. No third-party tracker is contacted from your browser.
They record anonymous page views and Core Web Vitals (loading and responsiveness metrics). They do not store your IP address and cannot link you across days or across sites. None of your calculator inputs are ever included.
No third-party tracking or selling of data
There are no third-party tracking scripts on the site, and nothing about you is sold or shared.
Changes and contact
If these practices change, this page will be updated with a new date. For any privacy question, email hello@effectivetax.co.uk.