Add a PDF Watermark
Enter your watermark text and select the pages to mark. Position it once per page or tile it across the page before downloading the PDF.
Runs locally in your browser ·
Enter your watermark text and select the pages to mark. Position it once per page or tile it across the page before downloading the PDF.
Runs locally in your browserChoose a PDF and stamp one line of text on every page or on a page range. The file is rewritten in this browser with pdf-lib and arrives as a new download; the original is left untouched.
The line is drawn as a picture of the text, so accented letters and scripts such as Japanese or Chinese keep their shape. That is also why it stays a single line: a very long sentence runs past the page edge instead of wrapping.
The watermark is one line of bold text at the size you choose between 8 and 180 pt, in the colour of the picker (green by default) and at your angle between -180 and 180 degrees. The default -35 degrees tilts the line down to the right; 0 is horizontal, and a positive angle lifts it up to the right.
Opacity is applied when the line is placed, so the default 24 percent reads as a light grey-green on white paper and 5 percent is the faintest setting the tool offers. The mark is an image, so it does not depend on the fonts inside the PDF and each page keeps its own background.
The four corners sit 28 pt from the edge of the page as the reader sees it. A page that carries /Rotate 90, 180 or 270 keeps the same visible corner and the line keeps its angle: the probe stamped a 0/90/180/270 file and all four pages carried the mark in the same place.
Tiled repeats the line across the whole page. The grid steps by the turned bounding box of one mark plus a small gap: on an A4 page the line CONFIDENTIAL at the default size lands three times in one column, and the next column is clipped at the paper edge. At 180 pt one mark is wider than the page, so only a corner of one repetition shows.
A range is read in the order you write it, so "5-3" runs backwards, and a page named twice is stamped once - the Pages figure counts the pages that were really marked. A number outside the document stops the run with a message instead of quietly choosing the nearest page.
The size, opacity and angle boxes are corrected to the figures that were drawn: an empty size draws 54 pt, 999 draws the 180 pt maximum, and an opacity of 0 draws 5 percent. The run button is held while a run is in progress, another file clears the sizes of the previous document, and a file replaced mid-run discards the result. Nothing is uploaded.