Privacy policy
The short version: your files stay on your device, we keep the minimum account data needed to run your proofs, and the only third-party cookie we use is one Google Ads cookie that measures whether our ads work — and only if you accept it.
Your files never reach us
When you create a proof, your file is read only by your own browser. It calculates a SHA-256 fingerprint locally and sends us that fingerprint alone. The file itself is never uploaded, never stored, and never transmitted.
This means we cannot read, recover, or hand over your documents, because we never receive them. The filename, file size, and file type you see on a certificate are metadata your browser sends alongside the fingerprint.
Account data
If you create an account we store your email address, your plan, and the proofs you have created. We use your email to send account and proof notifications, and to let you sign in.
If you enter an email before creating an account, we store it so the proofs you made can be moved to your account when you sign up.
Google Ads conversion cookie
If you accept cookies, we load Google Ads conversion tracking and it sets one cookie. Its only purpose is to measure whether our advertising works — that is, whether someone who clicked one of our ads later created an account or subscribed.
No file data is involved. The fingerprints of your documents, your filenames, and the contents of your proofs are never sent to Google. What is sent is that a signup or a purchase happened, and for purchases the amount and currency.
We do not use this for remarketing or ad personalization, and we run no analytics product. If you decline, or if you have not chosen yet, nothing from Google is loaded at all and no request is made to their servers.
You can change your choice at any time with the "Cookie settings" link in the footer.
Payments
Paid plans are processed by Stripe. Card details go directly to Stripe and never pass through our servers. We store the identifiers Stripe gives us so we can link a subscription to your account.
Questions or deletion requests
For any question about this policy, or to ask us to delete your account and its data, use the contact page.