Privacy and referral links

Nothing that identifies you. There are no accounts, no sign-up forms and no advertising or analytics trackers on this site.

The calculator runs in your browser. The car details you enter are not sent to us unless you create a share link, in which case they are part of that link's address and nothing more.

Your light or dark theme choice is stored in your own browser (local storage) so the site remembers it. It never leaves your device.

ratio is hosted on Vercel. Like any web host, Vercel processes standard request information such as IP address and browser type to deliver pages and protect against abuse. See Vercel's privacy policy for details.

Some tyre recommendations link to retailers such as Tyroola. These links pass through ratio (addresses starting /go/) and then on to the retailer. Once you arrive, the retailer and any referral network it uses may set their own cookies, including cookies that record that you came from ratio. Their privacy policies apply from that point.

Where a link is a referral link, ratio may earn a commission if you buy, at no extra cost to you. This never changes which tyres ratio recommends or the order they appear in, and referral links are labelled next to where they appear.

If this changes, for example if analytics are added, this page will be updated before it happens.