Privacy
Your photos go to a server to be measured and are deleted as soon as they are. Nothing is kept unless you press Share or Flag.
Draft of 3 October 2026, to be reviewed before launch.
Checking a card
When you check a card, your browser makes the photos smaller, removes their location and other camera data, and sends them through Cloudflare to Preslab's checker. The checker measures them in memory and deletes them when the measurement is done. It writes nothing to disk and keeps no log of what was in them. The result waits for your browser to collect it for about ten minutes, then it is gone from the server too.
What stays in your browser
Your recent checks, with their photos, are kept in this browser's own storage so you can open them again. They never leave it unless you share or flag a check. You can forget a check from the list, or clear the site's data in your browser's settings. On an iPhone, Safari may clear them after a week without a visit unless Preslab is added to the Home Screen.
What is kept on a server, and only if you ask
| When you | What is kept | For how long |
|---|---|---|
| Share a link | The result and the straightened card (front and back), at the link's address | Until you delete the link. Anyone with the link can see it. |
| Flag for review | Your photos, the result and your note | Until a person has reviewed it. A useful case may be kept to test future versions. |
| Say it looks right, or tell us the grade | That answer, the check's id and, for a grade, the company, grade and cert number | Kept to measure how well Preslab reads |
| Report a shared page | The page's address, the reason and your note | Until it is dealt with |
None of these carries your name, an account or your address. There are no accounts.
Cloudflare
Preslab runs on Cloudflare, which sees each request as it passes, as any host does.
Ads, paid links and cookies
Preslab shows no ads and sets no cookies. A result ends with links to grading supplies on Amazon. They are paid links: as an Amazon Associate, Preslab earns from qualifying purchases made after following one. Preslab sends Amazon nothing about you or your card, and nothing from Amazon loads on this site; once you follow a link, Amazon's own privacy notice applies. This page will say so before any of this changes.
Questions
Use "Report this page" on a shared result to ask for it to come down. For anything else about your data, the contact address will be listed here before launch.