Protect documents before ChatGPT and Claude

October 30, 2026 · Zecretly

In short: Replace names, addresses, account numbers and amounts with placeholders before you upload the file, then put the real values back locally afterwards. With Zecretly that takes four steps, entirely on your computer.

Why should I not upload documents as they are?

Documents and emails contain names, addresses and amounts. What you give to an AI service is afterwards governed by its provider. If you replace the details first, you never hand them over in the first place.

Whether you may give data to an AI service depends on your obligations, for example a professional secrecy duty or a contract with your clients. Zecretly does not answer that. If in doubt, ask your data protection officer or legal counsel.

How do I protect a document in four steps?

1. Protect the file. Drag the file into the Zecretly window, or right-click it in File Explorer and choose “Mit Zecretly schützen” (the menu entry is in German). For text, select it and press Ctrl+Alt+Z. The protected copy sits next to the original, for example as Letter.zecretly.docx.
2. Look at the copy. Zecretly does not catch every value. Read the protected copy before you upload it.
3. Upload it and let the AI work. Give the protected copy to ChatGPT, Claude or another service. It sees placeholders such as [PERSON_1] instead of the real details.
4. Restore the answer. Open the answer with Zecretly again. The local case file puts the real values back. Numbers that the AI has recalculated are converted back as well.

Which protection level fits?

Normal replaces personal details only, date and amount stay as in the original. Strong (default) shifts date and amount to other, matching values, so totals and shares stay consistent and the AI can keep calculating. Maximum shows date and amount as placeholders only. More at How Zecretly works.

What can Zecretly not do?

Paraphrases, text inside images and scanned PDFs without a text layer are not read reliably. With PDF, the layout is lost. And Zecretly does not catch every value, which is why step 2 asks you to look at the copy.