How to Watermark a PDF Online, Free
A watermark — DRAFT, CONFIDENTIAL, SAMPLE, or your own text — stamped across a PDF is one of the fastest ways to signal a document's status before it's finalized. Here's how to add one online, what settings actually matter, and what a watermark can't do for you.
Why Watermark a PDF
A watermark doesn't lock a file the way a password does — anyone can still open, read, and technically copy it. What it does is remove ambiguity: a reviewer, client, or student can't mistake a stamped "DRAFT" copy for a finished, approved version. That's the entire job it needs to do in most everyday cases.
- Draft documents sent for review before final sign-off
- Sample or preview files shared before payment or approval
- Confidential reports that need a visible status marker
- Ownership marking on proposals, mockups, or portfolios
How to Add a Watermark to a PDF
- Open the Watermark PDF tool. Go to tooltiny.com/watermark-pdf.html — no account needed.
- Upload your PDF. Drag and drop the file or click to browse.
- Type your watermark text. Common choices: DRAFT, CONFIDENTIAL, SAMPLE, or your company name.
- Adjust font size, opacity, and angle. See the settings guide below for the standard look.
- Preview, then download. The watermark is applied to every page, and the original file is auto-deleted from the server shortly after.
Free, no sign-up, auto-deleted after processing.
Choosing Angle & Opacity
The classic document-stamp look — the one that reads as professional rather than accidental — comes down to two settings working together.
Angle: 45 degrees
A diagonal watermark is instantly recognizable as intentional. Horizontal text at the top or bottom can look like a header instead of a status marker.
Opacity: 20–30%
Low enough that the underlying text stays fully readable, high enough that the watermark is unmistakable even in a quick glance or a printed copy.
Font size should scale with the page — a watermark that's too small gets lost, one that's too large can crowd out the content underneath it. Preview before downloading rather than guessing.
What a Watermark Won't Do
It's worth being precise about this, because it changes which tool you actually need:
- It won't stop copying or forwarding. Anyone with the file can still redistribute it.
- It won't survive determined removal. A low-opacity stamp can be cropped or edited out with enough effort.
- It won't lock the file. For that, you need password protection instead — a completely different mechanism that controls who can open the file at all.
If you need both — a visible status marker and restricted access — apply the watermark first, then password-protect the watermarked file.