Certscan opens a real TLS connection to the hostname you enter. Your hostname is used only to perform that check and is never stored — no database, no log, no cache. The result of the check is displayed to you in your browser session and discarded.
The site loads two font families from Google Fonts (Newsreader, IBM Plex Sans/Mono). Google's privacy policy applies to those requests. No other third-party service receives data from this site.
Because no hostnames, IP addresses, or user identifiers are stored, there is nothing to retain, delete, or export. The TLS connection result exists in your browser until you navigate away or reload the page.
If you have questions about data handling, contact details will be added here when the owner supplies them. At present no mailbox is available.