How to redact a PDF properly, and check that it worked
Why covering text in a PDF leaves it in the file, what real redaction does, a step-by-step walkthrough, and the checks to run before you send anything.
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Guides to working with documents privately
Practical guides to redacting, encrypting, editing and converting documents privately, without uploading them anywhere. Each guide says plainly what our tools do and don't do, and links to its sources.
How to check whether a PDF redaction really worked
Six checks anyone can run on a redacted PDF with free tools, what each one catches, and what they cannot prove.
How to edit a .docx file without uploading it anywhere
What happens to a document you open in an online editor, how in-browser editing differs, and an honest list of what survives a .docx round trip.
How to open and edit a .pptx file without PowerPoint
Desktop suites, online services and an in-browser editor compared for opening a .pptx deck, with the fidelity limits of each.
What "client-side" really means, and how to check a no-upload claim yourself
Three checks you can run on any web app that says it does not upload your files, and what each check can and cannot prove.
How to encrypt a document with AES-256 and a strong passphrase
What AES-256-GCM and PBKDF2 actually do, why the passphrase matters more than the cipher, and how to share an encrypted file without leaking the password.
How to OCR a scanned PDF without uploading it
How text recognition works, how to run it on a scanned PDF inside your browser, and what makes the difference between clean and messy results.
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