Watermark PDF
Stamp a diagonal, semi-transparent text watermark across every page. Type your text, upload the file, done.
Type the watermark text (default: DRAFT), then upload your PDF. Every page gets the same text, angled diagonally at 25% opacity — dark enough to notice, light enough that the page underneath stays readable.
Before you start
Three simple steps
Set watermark text
Type the text you want stamped on every page.
Upload PDF
Choose the file you want to watermark.
Download
Get your watermarked PDF instantly.
Why diagonal, not straight across?
A watermark placed flat along one edge is trivial to crop out — cut a strip off the page and it's gone. Diagonal, running corner to corner, means removing it damages the actual content too. This is why nearly every document watermark you've seen, ours included, runs at an angle instead of sitting neatly in a margin.
Privacy
Watermarking happens entirely in your browser. Your PDF is never uploaded to a server.
Common watermark text, and why local processing matters here specifically
Beyond DRAFT and CONFIDENTIAL: SAMPLE for portfolios sent before payment, DO NOT COPY for sensitive HR or legal files, INTERNAL USE ONLY and NOT FOR DISTRIBUTION in corporate contexts, ATTORNEY-CLIENT PRIVILEGED in legal correspondence.
Here's the thing about watermarking a document as CONFIDENTIAL, an NDA, or a draft term sheet: the whole point is that the content is sensitive. Running it through a tool that uploads the file to a server just to stamp a word on it works against the reason you're watermarking it in the first place. Since this tool never uploads the file, that contradiction doesn't apply — the watermark gets added the same way the document stayed private the whole time.
Continue with your PDF
Watermark PDF FAQs
What opacity does the watermark use, and can I change it?
It's fixed at 25% right now. That number isn't arbitrary — much lighter and a scanned or reprinted copy loses it entirely; much darker and it starts fighting with body text for attention. This falls in the 20-30% range generally recommended for CONFIDENTIAL/DRAFT stamps. Adjustable opacity is on the list for a future update.
Can I change the watermark color?
Not yet — it uses a fixed muted red. Color and font options are planned.
Will the watermark cover my text?
No. At 25% opacity the page content stays fully readable underneath — that's the whole point of using opacity instead of a solid stamp.
Can I watermark a password-protected PDF?
Not yet. Unlock it first, then upload it here.
Is my file uploaded anywhere?
No. Everything runs in your browser using JavaScript.
Why does it matter that this runs locally for a CONFIDENTIAL watermark specifically?
Because uploading a genuinely confidential document to a server just to stamp a warning label on it undercuts the reason you're marking it confidential in the first place. Processing it locally means the file never left your device at any point in the process.