Privacy Policy

Last updated: 13 August 2026

This page is provided for transparency and to explain how MarkPrep handles your data. It is written in plain English and is not legal advice.

What runs in your browser

MarkPrep converts your documents 100% inside your own browser using WebAssembly. There is no upload endpoint, no conversion server, no OCR API on our side, and no storage of your source files. Your source documents and their contents never reach our servers. Nothing about the file you convert is transmitted to us to perform the conversion.

The two labelled exceptions

There are exactly two features where data leaves your device, and both are labelled at the point of use in the interface so you always know when they apply:

• URL-to-Markdown. When you paste a public web address, we fetch that public webpage through a serverless proxy so it can be converted. Only the public URL you type is sent — your own documents are never sent. We use the proxy purely to retrieve the page you asked for.
• Bring-Your-Own-Key OCR (optional). If you choose to use OCR with your own AI provider key, a page from your document is sent from your browser directly to your own AI provider using your own key. We are not in that data path: we never see the key and never see the page. That exchange is between you and the provider you selected.

What we store for Pro accounts

You do not need an account to use the free tier. An account is only required for Pro. For Pro subscribers we store:

• your email address;
• your plan status;
• billing customer and subscription identifiers;
• a licence key.

We do not store your source documents or their contents as part of your account.

Encrypted sync

The optional encrypted-sync library stores only client-side-encrypted ciphertext that we cannot read — we never hold the encryption key. It syncs your outputs only, never your source files. Because the data is encrypted on your device before it reaches us, its contents are not readable by us.

Analytics

Our analytics are cookieless and privacy-friendly, which is why the site does not need a cookie banner. We do not track your file names, file sizes, or file contents.

Payments

Payments are handled by a third-party merchant of record (for example, Lemon Squeezy), which acts as the seller of record and handles VAT. We never see or store your card details.

Your local data

The free library saves up to 25 results in your browser’s IndexedDB, on your own device. This data stays on your device and is under your control; clearing your browser storage removes it.

Changes

We may update this policy from time to time. When we do, we will revise the “Last updated” date above. Significant changes will be reflected here so you can see what changed.

Contact

If you have questions about this policy, contact us at the email on our site (for example, support@markprep). You can also review our Terms of Service.