How to Add a Watermark to a PDF

To add a watermark to a PDF, upload the file, type your watermark text (or pick a preset like CONFIDENTIAL or DRAFT), adjust the size, font, colour, and opacity using the live preview, then click Apply Watermark to All Pages — the watermarked PDF downloads to your device, with no upload to any server.

When do you need to watermark a PDF?

A watermark serves two purposes: it signals the status of a document, and it discourages or complicates unauthorised copying. These are different problems with overlapping solutions, which is why a small set of standard watermark texts covers almost every real-world need.

• Sharing drafts for review — a DRAFT watermark makes the document status unambiguous, so reviewers know not to treat the content as final or forward it as authoritative
• Distributing sensitive documents — a CONFIDENTIAL watermark on an HR report, board pack, or financial summary signals handling requirements at a glance, even to someone who receives it second-hand
• Preventing unauthorised copying — a DO NOT COPY watermark adds visible friction to screenshotting, scanning, or republishing content without permission
• Sharing samples of paid content — a SAMPLE watermark on a report preview, course excerpt, or design asset clearly marks it as a demonstration version while the full document stays protected behind payment
• Tracking document versions — a custom watermark with a version number, date, or recipient name can help identify which copy was shared with whom if a document leaks
• Legal and compliance marking — certain regulatory contexts require documents to be marked with their classification or handling requirements before distribution

The problem with most online watermark tools

Watermarking is one of the most privacy-sensitive PDF operations. The documents people need to watermark — HR files, legal contracts, board reports, financial statements — are typically the documents that should be handled most carefully. Yet every major online watermark tool (iLovePDF, Smallpdf, Adobe Acrobat online) processes them server-side: your file travels to their infrastructure, gets processed, and comes back.

There are two privacy problems here. First, the file you are marking as CONFIDENTIAL is uploaded to a third-party server before you have even applied the watermark. Second, the tool learns something about the contents of your document from the type of watermark you are applying — CONFIDENTIAL on a 40-page PDF is a different signal than DRAFT on a two-page memo.

FixMyPDF adds watermarks entirely in JavaScript using pdf-lib, the same library that handles all other PDF operations on this site. The text is drawn directly onto each page's content stream in your browser. Nothing leaves your device. The CONFIDENTIAL watermark you add to your board pack never touches an external server.

How to add a watermark to a PDF step by step

1. 1
   Open the Add Watermark tool
   Go to fixmypdf.tech/tools/watermark.html. No sign-up required.
2. 2
   Upload your PDF
   Drag the file onto the drop zone or click to browse. The file loads in your browser only — nothing is transmitted anywhere.
3. 3
   Enter your watermark text
   Type any text in the Watermark text field. For common use cases, click one of the four preset chips — CONFIDENTIAL, DRAFT, DO NOT COPY, or SAMPLE — to fill the field in one click.
4. 4
   Customise the appearance using the live preview
   Choose a size (S/M/L/XL), a font (Sans-serif, Serif, or Mono), a colour from the swatches or the custom picker, and drag the opacity slider. The live preview panel updates instantly so you can see exactly how the watermark will look before applying it.
5. 5
   Click Apply Watermark to All Pages and download
   Press the Apply Watermark to All Pages button. The watermark is drawn diagonally across every page and a download prompt appears. Your original file is not modified.

Choosing the right watermark text

The four preset texts cover the most common document-marking scenarios. You can type any text you like, but the presets are one-click shortcuts to the most widely recognised standard labels.

For version tracking or tracking document leaks, include identifying information in the watermark text: the recipient's name, a date, or a version identifier. This is sometimes called a canary watermark — if the document is shared inappropriately, the watermark text tells you exactly which copy was leaked.

Customising size, font, colour, and opacity

The four appearance controls give you enough flexibility to match the watermark to the tone and purpose of the document, while the live preview lets you adjust without guessing.

Size

Four sizes are available: S (32pt), M (48pt, the default), L (64pt), and XL (80pt). The default 48pt is readable across most page sizes without overwhelming the document content. Use S for dense, text-heavy pages where readability matters, or XL for large-format documents where the watermark needs to be prominent even when printed at a reduced size.

Font

Three font families are available: Sans-serif (Helvetica, the default), Serif (Times Roman), and Mono (Courier). Sans-serif gives a clean, modern appearance and is the best default choice. Serif suits formal legal or financial documents where a more traditional look is appropriate. Mono is useful when you want the watermark to look technical or machine-stamped — useful for DRAFT or version markings on technical specifications.

Colour

Seven preset swatches are available: light gray, gray (the default), red, amber, blue, navy, and black. A custom colour picker gives you access to any colour. The default gray is the most neutral choice and works well across document types. Red is widely understood to signal an urgent or high-priority classification. A custom colour is useful when you want the watermark to match your organisation's brand.

Opacity

The opacity slider runs from 5% (barely visible) to 80% (bold and prominent), with a default of 30%. This is the most important setting to get right, because the ideal opacity depends on both the purpose of the watermark and the content of the document.

Tips for specific use cases

Distributing draft documents for review

Use the DRAFT preset at 25–35% opacity in gray or light gray. This keeps the marking visible without making the document hard to read during review. If you circulate multiple draft versions, add a version number to the text: "DRAFT v2" or "DRAFT 2026-06-11" so reviewers can tell which version they are looking at.

Marking board-level or legal documents as confidential

Use CONFIDENTIAL at 30–40% opacity in a dark colour (navy or black). Pair the watermark with password protection using the Protect PDF tool — the watermark communicates the document status even after the file is shared, while the password prevents unauthorised access in the first place.

Protecting sample or preview content

For content you are sharing as a teaser before payment, use SAMPLE at higher opacity (50–60%) so the marking is impossible to crop out or overlook. A more prominent watermark on a sample makes the value of the full, unmarked document clearer.

Combining watermarking with compression

Watermarking adds only a small amount of data to the file. If you want to share a compressed watermarked version, compress first with the Compress PDF tool, then add the watermark. This order is more efficient because the compressor does not need to work around the watermark text data.

Combining watermarking with rotation

If your document has incorrectly oriented pages, rotate them to the correct orientation before watermarking. The watermark is applied diagonally relative to how the page is stored in the PDF — correcting orientation first ensures the text runs across the page at the expected angle.

Frequently asked questions