Add Watermark

Stamp DRAFT, CONFIDENTIAL or your own words across a PDF's pages.

Runs in your browser. Nothing is uploaded — your input is processed on this device and discarded when you close the tab.

Your file

Drop a PDF here or click to browse. One file at a time, up to 50 MB. Everything is processed on this device only — no file is uploaded.

Watermark text

Opacity (0.1 faint – 0.9 strong)

Rotation Flat (0°) Diagonal up (45°) Diagonal down (315°)

Font size (points)

Colour Grey Navy Blue

Layout One watermark, centred on each page Tiled grid across each page

Page range (optional)

Comma-separated pages and ranges numbered from 1. Blank means the whole document.

Apply watermark

A watermark is the word printed across a page that tells a reader how to treat the document: DRAFT before it is final, CONFIDENTIAL when it should not travel, SAMPLE when it is a specimen. This tool stamps one word or short phrase across the pages of a PDF you already have, with control over how strong it looks, how large it is, whether it runs flat or diagonally, and whether it appears once in the middle of each page or repeated in a tiled grid. It runs entirely in your browser: the file is read on your device, stamped in the tab, and returned as a download, with nothing uploaded at any point.

That local processing matters for exactly the documents that need watermarks. The drafts and confidential files people stamp are the ones they least want copied onto an unknown server, so the tool is built to never ask for that trade. Add the file, set the wording and strength, and download the stamped copy — the original on your device is untouched, so you can re-run with a different wording as the document's status changes.

How to use Add Watermark

1. Open with the document you want stamped. Drag it into the workspace, or click through to your folders and select it there. Stamping happens one document at a time and the file may weigh up to 50 MB; you will be told its page count immediately, and a file that arrives damaged or under password protection is called out before you start choosing wording.
2. Write the watermark text. Keep it short — a word or two reads most clearly at a glance ("DRAFT", "CONFIDENTIAL", "DO NOT COPY"). Up to 80 characters are accepted, but a long sentence shrinks into illegibility at any sensible size.
3. Set the opacity. Opacity runs from 0.1 (a faint suggestion) to 0.9 (nearly solid). Around 0.2–0.35 is the usual range for a draft stamp: visible on every page, quiet behind the text.
4. Choose the rotation. Flat (0°) reads like a banner; the two diagonal presets (45° and 315°) are the classic watermark angles and are harder to ignore — or to crop away.
5. Set the size and colour. Font size is in points; 48 is a good starting point for a single centred word on A4. Grey is the conventional choice, with navy and blue offered for documents that will be photocopied, where grey can vanish.
6. Pick the layout and pages. "Single" centres one stamp on each chosen page; "Tiled" repeats it in a grid across the whole page. Use the range box (for example 1-4) to watermark only part of the document, or leave it blank for every page.
7. Apply and check. The status line reports how many pages were stamped. Open the download and check a dense text page: the watermark should sit visibly behind the content without fighting it.

Features

• Custom watermark text up to 80 characters, drawn in a bold standard typeface.
• Opacity adjustable from 0.1 to 0.9, applied identically to every stamp.
• Three rotations: flat, diagonal up (45°) and diagonal down (315°).
• Font size from 6 to 200 points, and three colours (grey, navy, blue).
• Single centred layout, mathematically centred on each page even when rotated, or a tiled grid that repeats the stamp to every corner.
• An optional page range, so appendices or a title page can be left unstamped.
• Mixed page sizes are handled per page: every stamp is planned from that page's own dimensions.
• Processing runs entirely in the browser; the original file is never modified.

Worked example

Picture a three-page A4 document, stamped with the text CONFIDENTIAL at rotation 45°, opacity 0.3, size 48, in grey, using the single layout. The result still has three pages, the original text of every page is unchanged, and the word CONFIDENTIAL is present on all three pages — the test suite for this tool extracts the text of the stamped file and finds the watermark alongside each page's original content, page by page. With the tiled layout instead, using 60-point text measured at 200 points wide with a 40-point gap, an A4 page takes 27 stamps — 3 across by 9 up — a figure the tests verify from the tool's own tiling maths, which lays cells from the bottom-left corner and lets the edge cells run to the page corners so no unstamped margin survives.

Common errors and limitations

• The watermark is text only. There is no image or logo watermark, and no font choice — a bold standard typeface is used so the stamp renders identically everywhere.
• The stamp is drawn on top of the page content as a translucent layer. It discourages casual copying and marks a document's status, but it is not a security feature: anyone with a PDF editor can remove or cover a drawn-on stamp. For protection that travels with the file, use a password tool as well.
• Tiling density is derived from the text size and width with a fixed comfortable gap; you cannot set the gap or the tile angle separately from the rotation — one rotation governs every stamp, single or tiled.
• One wording, one style per run. Pages that need a different word (for example DRAFT on the body and SAMPLE on an appendix) need one run per wording, using the range box.
• Encryption closes the door to this tool as well: a document guarded by a password first has to be exported without that guard, by the software that set it, before any stamping can happen.
• Expect to work on one document per run and to stay within 50 MB, since the stamping is performed inside your browser tab rather than on a machine elsewhere.

• The watermark hides the text. Opacity too high, or a large size on a dense page. Fix: drop the opacity toward 0.2 and check a text-heavy page, not the title page, before deciding.
• It looks fine on screen but vanishes in print. Light grey at low opacity can fall below what a printer or photocopier reproduces. Fix: raise the opacity, or switch to navy, which survives copying far better.
• The "watermark" is expected to protect the file. A drawn stamp can be removed with editing software; it marks intent, it does not enforce it. Fix: treat the watermark as communication, and add a password if the document genuinely must not be opened or altered.
• A long sentence is squeezed across the page. Watermarks are read in a glance, at an angle. Fix: shorten the text to a word or two and let the size come down.

Frequently asked questions

Related PDF tools

Prefer everything on one page? The original PDF Toolkit merges, splits and rearranges with one shared file list. The full suite is indexed on the PDF Tools hub.

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