Watermark PDF
Diagonal text stamp, opacity control.
How to use
Drop PDFs into Watermark PDF: set Text and Opacity %, press Run, and PaperFlux processes everything with pdf-lib and pdf.js engines loaded lazily on your device — progress bar and cancel included. You get an instant result plus one-click download; originals are never uploaded, so DevTools Network stays clean.
Steps
- Open the tool below (or scroll to the interactive Watermark PDF).
- Set Text and Opacity % PDFs.
- Press Run (Ctrl+Enter) and watch the progress bar.
- Download the result, or copy and share the link.
FAQ
Is Watermark PDF really free?
Yes — free with no signup, no credits and no limits on this tool. It is supported by clearly labeled ads placed away from the buttons, never by paywalls.
Do I have to upload my files to use Watermark PDF?
No. Your files are read with the File API and processed with pdf-lib and pdf.js engines loaded lazily on your own device — there is no upload endpoint at all. Open DevTools, go to Network, and watch: your file never leaves the tab.
What should I enter in "Text"?
Put your text here — for example: DRAFT. Leave the defaults first to see how it works, then adjust. Every field is validated with a plain-language message if something is off.
I normally use Smallpdf — why switch?
If you are tired of upload queues, task limits, watermarks and accounts demanded for batch jobs, PaperFlux is the alternative: local pdf-lib operations with verified page counts — no queues, no watermarks, no uploads.
How accurate is Watermark PDF?
Everything runs on your device, so results are instant and repeatable — same inputs, same outputs, no server involved.
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Free alternative
Free alternative to iLovePDF and Smallpdf for merging, splitting and converting PDFs — local pdf-lib operations with verified page counts — no queues, no watermarks, no uploads. iLovePDF vs Smallpdf vs PaperFlux.
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