Apchukso ~/watermark
All tools Watermark
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TOOL / WATERMARK

Make it clear
it's yours.

Set the text, opacity, and size just the way you want.

Drop a PDF here or click to choose
1 PDF file
🔒
Your files never leave your device. Apchukso has no server that receives files. Everything is processed right here in this browser.
How to check for yourself
  1. With this page open, turn off Wi-Fi and try it. It still works.
  2. Press F12 → open the Network tab and run it. Aside from small analytics requests, there's no transfer anywhere near the size of your file.
Next steps
PDF↓
Compress itLighten your watermarked file
✂
Split pagesExtract just the part you need
PW
Lock with a passwordDouble up on protection
How it works: The open-source pdf-lib library draws semi-transparent text, rotated 45 degrees, directly onto each page. The watermark text is set in the embedded Nanum Gothic font.

More about PDF watermarks

Use it to stamp "DRAFT" on a draft contract, or to add a copyright notice or your name and organization to discourage unauthorized sharing.

How to use

  1. Choose a PDF
  2. Enter the watermark text, opacity, and font size
  3. Click "Apply watermark" and download the result

FAQ

Q. Can I add a logo image?

Right now, only text watermarks are supported.

Q. Can I change where the watermark goes?

For now, it's fixed diagonally across the center of each page.

Related tools

Merge PDF → Compress PDF →