Watermark PDF Online

Novaxera's Watermark PDF tool stamps your text diagonally across every page of a PDF, using “CONFIDENTIAL” if you leave the text empty. It is free, needs no signup, and the watermark is written into the page content rather than added as a separate layer.

Select a PDF to watermark

PDF · up to 50 MB · drag & drop or browse

Adding watermark...

This usually takes a few seconds.

Free · No signup · No watermark · Files deleted automatically within 60 minutes

Watermark PDF at a glance

The key facts about Novaxera's Watermark PDF tool.

Input
One PDF plus watermark text (default: CONFIDENTIAL)
Placement
Every page, centered, rotated 45° diagonally
Style
Gray Helvetica text at 15% opacity
Size
7% of each page's shorter side, so it scales with page size
Output
PDF with the watermark written into the page content
Price
Free — no signup
Max file size
50 MB per file
File deletion
Upload deleted right after processing; result deleted within 60 minutes
Works on
Any modern browser — Windows, macOS, Linux, Android, iPhone

How to add a watermark to a PDF

  1. Upload your PDF

    Select or drag one PDF of up to 50 MB into the upload box.

  2. Type the watermark text

    Enter words such as DRAFT, SAMPLE or your company name. Leave the box empty to use CONFIDENTIAL.

  3. Apply the watermark

    Novaxera adds the text to every page on its server.

  4. Download the result

    Download the watermarked PDF within 60 minutes.

How Novaxera's Watermark PDF works

Novaxera's Watermark PDF tool draws your text on every page of the document in one fixed style: centered, rotated 45° diagonally, gray, at 15% opacity, in the Helvetica font. The font size is 7% of the page's shorter side, so the watermark looks proportionate on A4, US Letter or larger pages. At 15% opacity the text stays readable as a mark while the content beneath it remains legible.

Novaxera writes the watermark directly into each page's content stream instead of adding a separate annotation layer that a viewer can switch off. That makes it harder to remove casually, but a watermark is a visual deterrent, not copy protection: advanced PDF editors can still edit it. For access control, combine it with Novaxera's password protect PDF tool so only people with the password can open the file.

Why use Novaxera's Watermark PDF

Every page covered

The watermark is applied to all pages in a single run, with no pages skipped.

Scales with page size

Font size is 7% of each page's shorter side, so mixed page sizes get proportionate marks.

Readable underneath

Gray text at 15% opacity marks the page while keeping the original content legible.

Sensible default

Leave the text empty and the tool stamps CONFIDENTIAL automatically.

Part of the page

The text is written into the page content, not a separate layer a viewer can toggle off.

Common use cases

Draft contracts

Mark versions under negotiation as DRAFT so nobody mistakes them for the signed copy.

Confidential reports

Stamp CONFIDENTIAL on board papers, HR files or financial reports before circulating them.

Portfolio samples

Add SAMPLE or your name to design or writing samples sent to prospective clients.

Sharing with a named recipient

Put a client or company name on a document to show who it was issued to.

Limitations to know

  • Watermarks are text only; image and logo watermarks are not supported.
  • Position, color, size and opacity cannot be changed: every watermark is centered, diagonal, gray and 15% opaque.
  • Helvetica covers Latin characters, so Arabic, Chinese and other non-Latin scripts may not display correctly in the watermark.
  • Advanced PDF editors can still edit the watermark, so pair it with PDF password protection when access matters.

Tips for better results

  • Keep the text short, such as DRAFT or CONFIDENTIAL, because the font size is fixed relative to the page and long phrases run across more of it.
  • If your PDF is password-protected, first unlock the PDF with its password, then add the watermark.
  • Need the mark only on some pages? Split the PDF into pages, watermark the pages you need, and merge the PDF files back together.
  • Keep an unwatermarked original, because the mark is written into the page content of the result.

Frequently asked questions

How do I add a watermark to a PDF for free?

Upload the PDF to Novaxera's Watermark PDF page, type your watermark text and download the result. The text appears centered and diagonal on every page. The tool is free, needs no account and accepts one PDF of up to 50 MB per run.

What does the watermark look like?

Novaxera's watermark is gray Helvetica text at 15% opacity, centered on the page and rotated 45° diagonally. Its font size equals 7% of the page's shorter side, so it scales with the page. These settings are fixed; there are no options for position, color, size or opacity.

What text is used if I leave the watermark empty?

Novaxera's Watermark PDF tool uses the word CONFIDENTIAL when the text box is left empty. To use different wording, such as DRAFT, SAMPLE, COPY or a company name, type it in the text box before applying the watermark. Whatever text you choose appears on every page in the same diagonal style.

Can I add a logo or image watermark?

No. Novaxera's Watermark PDF tool supports text watermarks only. Image and logo watermarks are not available. A practical alternative is to type your company or brand name as the watermark text, which then appears diagonally in gray on every page of the PDF.

Can a Novaxera watermark be removed?

Not casually, but it is possible with advanced tools. Novaxera writes the watermark into each page's content instead of a separate removable layer, yet advanced PDF editors can still edit it. Treat the watermark as a visual deterrent and add a password if you also need access control.

Does the watermark support Arabic or Chinese text?

Not reliably. Novaxera's watermark uses Helvetica, which covers Latin characters, so Arabic, Chinese and other non-Latin scripts may not display correctly in the watermark. Latin-script words such as CONFIDENTIAL, DRAFT or a brand name work as expected.

Are my PDFs safe when I watermark them online?

Yes. Novaxera's Watermark PDF tool receives your file over encrypted HTTPS, deletes the original upload once the watermark is applied and deletes the watermarked result automatically within 60 minutes. Files are not shared or used for anything else.

Can I watermark a PDF on a Mac or iPhone?

Yes. Novaxera's Watermark PDF tool works in any modern browser on macOS, iPhone, iPad, Windows, Android and Linux. Nothing needs to be installed: upload the PDF from your Files app or Finder, enter your watermark text and download the watermarked file to your device.

Related guides

Related tools

Protect PDF

Encrypt a PDF with AES-256 and an open password

Unlock PDF

Remove a known password from a PDF you are allowed to open

Split PDF

Turn every page of a PDF into a separate file

Merge PDF

Combine two or more PDFs into one document

Edit PDF

Change existing text in a PDF, including Arabic, line by line

Last updated · Maintained by Ghaith Alali · Facts on this page describe how Novaxera's Watermark PDF tool currently works. · Privacy policy