Privacy
The checker runs in your browser. Nothing you type into it is sent anywhere, stored, or seen by us.
What is collected
Nothing that identifies you. There is no account, no sign-in, no contact form and no newsletter. The site asks for no personal information and has nowhere to put any.
The checker
The tax code and the optional pay figure you type into the checker are processed entirely inside your own browser. They are not transmitted to this site or to anyone else, they are not written to storage, and they are not visible to us. Closing the tab discards them.
This is a property of how the tool is built rather than a policy commitment: the decoding logic ships to your browser as part of the page, and the page has no server to send anything to. It is also unaffected by anything in the next section — what you type is not part of what is measured.
Analytics
The site loads Google Analytics 4 to count visits. A Consent Mode v2 default runs ahead of the tag and denies analytics storage, advertising storage, advertising personalisation and personalisation storage for every visitor in every country, with no regional exception — so GA4 runs cookieless: no analytics cookie, and no identifier stored on your device. There is no consent banner here, of ours or Google’s, because there is nothing to grant; the denial is permanent rather than waiting on a choice you have not made yet.
What Google does receive on each page view is the page address, the referring page, an approximate location derived from your IP address, and your device and browser type. The tag itself is fetched from googletagmanager.com, so your IP address is visible to Google as part of that connection — cookieless is not the same as anonymous, and an IP address is personal data under the UK GDPR even when it is not stored. The legal basis is our legitimate interest in aggregate, cookieless measurement of how the site is used. This site publishes no contact address, so rather than point you at one that does not exist: the control it can actually offer is your own — blocking the script in your browser settings or with an extension stops the measurement for you and leaves everything else on the site working.
Google’s own handling of that data is described at policies.google.com/privacy. The measurement tag is switched off entirely for any browser carrying our internal-testing flag, which the cookies page describes.
Advertising
There is no advertising on this site and no advertising code in it.
Third parties
The Google Analytics tag described above is the only thing on a page here that reaches another host. There are no third-party fonts, no embedded video, no social widgets and no other third-party scripts.
Hosting
Like any website, the server that delivers these pages processes the request needed to send them to you. That is ordinary web-server operation and is not used to build a profile of you.
Links out
Pages here link to GOV.UK and to legislation.gov.uk. Those sites have their own privacy notices and this one does not govern them.
The figures and rules on this site are taken from the Income Tax (Pay As You Earn) Regulations 2003, the Income Tax Act 2007 and HMRC’s published guidance, and are shown as they were found. They have not been signed off by a reviewer. Where the law and HMRC’s naming differ, the page says which is which rather than blending them. For anything that affects a decision, the cited document governs and this site does not.