A diagonal "CONFIDENTIAL" or "DRAFT" stamp across every page is a quick, visible way to mark a document's status before it's shared — common for drafts under review, internal-only reports, or work samples you don't want quietly redistributed.
Steps
- Open Watermark PDF and add your file.
- Type the watermark text — "CONFIDENTIAL," "DRAFT," a company name, whatever fits.
- Adjust the opacity slider so it's visible but doesn't obscure the content underneath.
- Run it — the watermark applies diagonally across every page.
What a watermark actually protects against
A text watermark is a visible deterrent and a status marker, not an access control. It makes clear at a glance that a document is a draft, confidential, or otherwise not the final/public version — useful for internal review, work samples, or anything where the label itself carries meaning. It does not prevent someone from opening, copying, or redistributing the file; it just marks it while they do.
If the goal is actually hiding specific sensitive content rather than labeling the whole document, that's a different job — see Redact PDF, which blacks out and flattens chosen areas so the underlying text is genuinely removed, not just visually covered.
A tip on opacity
Low opacity (light, subtle) keeps the underlying text fully readable with the watermark just visible enough to notice. Higher opacity makes the watermark impossible to miss but can make dense text harder to read through it — for text-heavy documents, err toward the lighter end unless the watermark needs to be unmissable.