PDF Watermark
Add a text watermark to a PDF — pick the words, size, opacity, rotation, color and placement (centered, tiled or bottom), then download the result.
Drop a PDF here or click to choose
Local processing only — the file never leaves your device.
What is it
A watermark is a semi-transparent label drawn over every chosen page. With pdf-lib the text is embedded as vector glyphs, not pixels, so the watermark stays crisp at any zoom level and the file size barely grows. The original page content is never modified — only a new text layer is painted on top.
Notes & fun facts
The idea of marking documents with faint text is centuries old — paper mills literally wove their name into the sheet. A digital watermark does the same trick more politely: it stays readable enough to claim the file, yet translucent enough not to fight with the content.
Origin & history
Physical watermarks date back to 13th-century Italian papermakers. In computing, the term was borrowed for visible stamps in the 1980s document workflows, and PDF editing libraries like pdf-lib (2018) make the effect a one-liner that runs fully in the browser.