Watermark PDF pages with Latin text or a PNG you supply
Watermark PDF pages with a text stamp or a PNG you supply. Text is drawn in Helvetica, Times, or Courier. Characters outside Latin-1 are refused. You choose centre, a tiled pattern, or a corner, and an opacity from 0.05 to 1. The stamp is drawn on the pages you name.
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or drop / paste
How to watermark PDF pages
- Add one PDF. If it is encrypted, use the password you already know.
- Choose Text or Image. For text, type the words, pick Helvetica, Times, or Courier, and set size, colour, and rotation. For an image, supply a PNG.
- Set opacity between 0.05 and 1. The default is 0.18, which is faint. Position is Centre, Tiled, Top left, or Bottom right.
- Set Pages if the stamp should not cover every page. The syntax is 1-3, 5, 8-. Leave it blank to stamp the whole document.
- Press Add watermark and download the PDF. Text longer than 60 characters is cut. A character outside Latin-1 stops the job and tells you to remove it or add the words as an image.
Watermark PDF options explained
Text uses the standard PDF fonts: Helvetica, Times, or Courier. Those fonts cover Latin-1. Accented letters in that set are accepted. Scripts outside it, including emoji, are refused rather than drawn as missing boxes. The message says to remove those characters or add the words as an image.
Position Centre places one stamp in the middle. Tiled places a 3 by 3 pattern. Top left and Bottom right are the corners. Rotation applies to text, from -90 to 90 degrees, default 45. The PNG is stamped at the same positions, at about 35 percent of the page width, and the text rotation is not applied to it.
Opacity is clamped between 0.05 and 1, so a fully invisible stamp is not offered. Size for text runs from 8 to 160, default 48. Colour is a hex value, default #8a8f86. The Pages field limits which pages are stamped.
Text stamp and image stamp
The text stamp is real PDF text in a standard font, drawn on top of the copied pages. It is not a render of the whole page. Existing text stays selectable. The stamp itself is also text, unless you used a PNG.
The image stamp is a PNG you supply. It is embedded and drawn at the position you picked, with the opacity you set. It does not pick up the text rotation angle. If you need the words in a font these three cannot draw, put those words in the PNG instead. That is the path the error message points to.
A stamp is not a lock. Anyone who can edit the PDF can cover it or crop it. Password protect PDF is a different job, and even there the permission flags are advisory in some viewers. A watermark does not prove who made the file.
What the stamp does not do
It does not remove the text underneath. A faint stamp over a paragraph leaves that paragraph readable and selectable. If you needed the words gone, a watermark is the wrong tool, and a crop is not redaction either.
It does not translate. Latin-1 is the limit of the built-in fonts this page can embed. The producer line on the saved file is still Upload Nothing (uploadnothing.com), which is separate from the stamp you typed.
Limits, formats and output
| Accepted input | |
|---|---|
| Files per batch | 1 |
| Soft size warning | 200 MB or 1,000 pages |
| Hard stop | 500 MB total in memory |
| Output | PDF, or a ZIP when there is more than one file |
| Account | None. The tool runs in this tab. |
Your file never leaves your device
Your watermark is drawn by a script running in this tab. The work runs in a Web Worker in this tab, using WebAssembly for the heavy parts, and the result comes back as a local blob. This site does not upload the file, store it, or log its name.
To verify: load the page, turn on airplane mode, and drop the file again. It still finishes. Or open DevTools, choose Network, and watch the run: there is no upload. The architecture is described on How it works.
Frequently asked questions
Why was my text refused?
A character was outside Latin-1. Helvetica, Times, and Courier cannot draw it. Remove that character, or put the words in a PNG and switch Watermark to Image. The job stops on purpose instead of skipping the glyph. Text past 60 characters is cut rather than refused.
Can I use my own font for the words?
Not as live text. The text mode offers Helvetica, Times, and Courier only. A PNG watermark can carry any lettering you have already drawn, because the PNG is an image. The image is placed at about 35 percent of the page width.
Where can the stamp sit?
Centre, Tiled, Top left, or Bottom right. Tiled means nine copies in a 3 by 3 grid. Rotation, between -90 and 90 degrees, applies to the text stamp. The default angle is 45 degrees. The PNG uses the position and the opacity, not that angle.
How faint can it be?
Opacity runs from 0.05 to 1. The default 0.18 is a light stamp. 1 is solid. Values under 0.05 are raised to 0.05, so you cannot save a stamp that is present and invisible. Lower the size as well if the words dominate the page.
Can I stamp only the first page?
Yes. Set Pages to 1. Use 1-3, 5, 8- for a longer set. A blank field stamps every page. Odd and even are not separate switches on this page. List the page numbers if you need a pattern.
Does the watermark lock the file?
No. It is ink on the page, text or a PNG. It does not encrypt the file and it is not a signature certificate. Protect PDF encrypts with AES-256. Sign PDF places a flat image of a name and says plainly that it is not a certificate.
Last updated 2026-09-26. By Tam.