How to Add a Watermark to a PDF: Text, Logo and Opacity

A watermark is a visible label: “DRAFT”, “COPY”, “SAMPLE”, or a faint logo. It tells the reader the status or source of a document. This guide explains exactly what the Add Watermark tool can do, walks through one real job (marking pages 3–6 of a report as DRAFT), and is honest about what a watermark will not do for you.

What a watermark is good for, and what it is not

Good for: showing that a file is a draft, labelling a sample or a review copy, and adding a recognisable logo so a printout is clearly yours.

Not a protection measure. In our test the watermark was written into the page as ordinary PDF text. A text-extraction tool picked the letters up, and anyone with a full PDF editor can select and delete it. A watermark does not stop copying, does not prove ownership and is not a legal safeguard. If you need to restrict who can open a file, use Protect PDF to add a password; if you need to remove information, delete it rather than covering it.

The settings, in the order you will use them

Setting	Range in the tool	Notes from testing
Text / Image	Two modes	Text uses Helvetica Bold. Image accepts PNG, JPG or WebP.
Text	Up to 80 characters	Latin letters, accented letters, digits and common symbols only. Bangla text showed a warning and the Add button stayed disabled.
Font size / Color	8–200 pt, any colour	Default 56 pt red.
Layout	Center or Tiled	Tiled repeats the text across the page in offset rows.
Image size	10–100% of page width	Image mode only; the image is centred.
Opacity	5–100%	15–25% is readable without hiding the content.
Angle	−90° to 90°, 5° steps	45° is the default diagonal.
Pages	Blank = all pages, or a range like 1-3	Commas also work, e.g. 2, 5-7.

There is no position control: text and images are always centred (or tiled), not placed in a corner. If you need a small mark in a corner, an image watermark at 10–15% width is the closest option, and it will still be centred.

Worked example: “DRAFT” on the pages still under review

1. Open Add Watermark and choose the PDF.
2. Leave the mode on Text and replace CONFIDENTIAL with DRAFT.
3. Choose Tiled, set Opacity to 20% and keep the angle at 45°.
4. In Pages, type 3-6, the sections that are not final.
5. Press Add watermark and download yourfile-watermarked.pdf.

What the test showed

Date	22 October 2026
Environment	Google Chrome 155 (headless) on Linux x86_64, desktop viewport 1280×900, PDFroo build of 22 October 2026
Input	Fictional 12-page report (9.7 KB) with a landscape page 4, 12 bookmarks and one internal link
Output	12 pages, 10.0 KB. Only pages 3–6 carried the watermark, including the landscape page; pages 1–2 and 7–12 were unchanged. The bookmarks and internal link were kept.
Text layer	pdftotext found the watermark letters on pages 3–6, so the watermark is selectable, searchable text and can be removed with an editor.
Non-Latin text	Typing Bangla showed “Text watermarks support Latin characters only…” and blocked the run. The tool suggests using a PNG of your text as an image watermark instead.

More on how we test is in our testing methodology.

Using a logo instead of text

Switch to Image, choose a PNG with a transparent background, set the size and keep the opacity low (10–20%). JPG logos have a solid background box, which shows as a pale rectangle. The image is centred and rotated by the same angle setting, so set the angle to 0° for an upright logo.

Problems and fixes

• The watermark hides the text: lower the opacity or use a lighter colour. Grey (#888888) at 15% is a safe start.
• Wrong pages were marked: page numbers refer to the position in the file (page 1 = first page), not to numbers printed on the page.
• Tiled text looks crowded: reduce the font size; spacing follows the text size.
• A form will not accept the file: some portals reject files with marks over the content. Upload the clean original instead.

Before you send it

• Scroll through the downloaded file; the preview only shows page 1.
• Print one page if the document will be printed, because opacity can look lighter on paper.
• Keep the unwatermarked original for the final version.

For long documents, adding page numbers helps reviewers refer to the draft pages.