How to use this tool
Step 1: Upload PDF
Select the PDF file you wish to watermark.
Step 2: Upload Watermark
Choose the PNG or JPG image you want to overlay.
Step 3: Position & Style
Configure watermark scale, position, and transparency.
Step 4: Process & Save
Save the watermarked PDF locally.
Frequently Asked Questions
Can I make the watermark semi-transparent?
Yes, you can adjust the opacity slider from 0% to 100% to blend the watermark perfectly with the page content.
Are my files uploaded?
No. The watermarking library processes files strictly inside your browser memory, keeping your documents and watermarks private.
Are my PDF files uploaded to any server?
No. Your PDF files are processed entirely in your web browser using WebAssembly. Your files never leave your device.
Is there a limit on the file size or page count?
No. Since the processing runs locally on your computer, there are no hard limits enforced by our server. It only depends on your system's memory (RAM).
Is this PDF tool completely free?
Yes, all PDF tools on Zaeyon are 100% free with no limits, no registration, and no ads or watermarks.
Users also use
Why Zaeyon?
Private, free, and browser-based — no account, no uploads, no compromises.
Zero Uploads
Your files never leave your device. All processing happens locally in your browser memory — nothing is sent to any server.
100% Free Forever
No subscriptions, no hidden fees, no daily limits. Every tool on Zaeyon is permanently free to use without an account.
Instant & Powerful
Powered by WebAssembly — the same low-level technology used in native apps — so processing is fast even for large files.
Works Offline
Once the page loads, the WebAssembly engine runs entirely on your device. No internet connection needed to process files.
Works Everywhere
No software installation required. Runs directly in your browser on Windows, Mac, Linux, iOS, and Android.