Sending a contract draft to a client who's known to forward things? You want DRAFT splashed across every page before it leaves your machine.
Watermarks aren't just for branding. They're how you signal status — draft, confidential, sample, expired — so a printed page can't be mistaken for the final.
Decide: text or image
Text watermarks (DRAFT, CONFIDENTIAL, SAMPLE) are crisp at any zoom and read at a glance. Image watermarks (a logo, a stamp graphic) carry brand weight but need a high-resolution PNG with transparency or they'll look blocky.
For anything legal or status-related, go text. For marketing collateral, a faint logo behind the content is usually the move.
Open the file and place the watermark
Drop your PDF into the editor. Choose Watermark, type the word (or upload the PNG), and pick a rotation — 45 degrees diagonal is the convention for DRAFT and CONFIDENTIAL stamps.
Set opacity around 20-30% so the watermark reads clearly but doesn't fight the underlying text. Higher than 40% and your document becomes hard to actually read.
Apply to the right pages
By default the watermark hits every page. Sometimes that's wrong — you might want the cover left clean, or only the body pages stamped. The editor lets you specify a range (e.g. pages 2-end).
If you're producing several drafts and want each version watermarked differently, run the file through once per version. You can also batch-merge variants together for review.
Flatten before sending
Watermarks added as a layer can sometimes be removed by a determined recipient. Flatten the PDF on save — Flint does this automatically — so the watermark fuses with the page content. Anyone trying to edit it back out has to redact pixel-by-pixel.
For genuinely sensitive material, follow up with a password to limit who can open the file at all.
FAQ
What's the best opacity for a watermark?
20-30% for a diagonal DRAFT or CONFIDENTIAL stamp. 10-15% for a background logo. Above 40% and the watermark starts competing with your content for the reader's attention.
Can I remove a watermark later?
If you keep the original PDF, yes — just re-watermark the original. Once a watermark is flattened into the file, removing it cleanly requires redaction and is rarely worth the effort.
Will my logo watermark work on every page?
Yes, as long as it's a transparent PNG. JPEGs have white backgrounds that block the underlying content. Stick to PNG or SVG for logos.
Can I watermark a 200-page document in one go?
Yes. Flint applies the watermark to every page in a single pass — 200 pages takes a few seconds.
A watermark is the quickest way to mark intent. Open your file in Flint's PDF editor, pick text or image, set the opacity, and ship it with confidence.