How to use Add watermark
Add your PDF.
Type your watermark text and choose its size, colour and angle.
Press "Add watermark" and download the result.
Questions
Why add a watermark to ID or certificate copies?
Writing something like "Only for XYZ bank KYC" across a copy makes it harder for anyone to misuse it elsewhere.
Which characters can I use?
English letters, numbers and common symbols. Other scripts are not supported yet.
Are my files uploaded to a server?
No. Dekiko processes your files inside your own browser. They are never uploaded, so nobody else can see them, and they are gone when you close the tab.