💧 PDF Watermark

PDF watermark, in plain terms

A PDF watermark is a semi-transparent mark — text like CONFIDENTIAL or an image like your company logo — overlaid on every page of a PDF to signal ownership, status, or restricted distribution.

At a glance

• Two modes. Text (font + size + colour + opacity + position + rotation) or Image (PNG or JPG logo, opacity + scale).
• Every page, one pass. The watermark is applied to all pages of the input PDF.
• Fonts. Helvetica, Times Roman, and Courier — the three standard PDF fonts that render identically everywhere.
• Positions. Diagonal (rotated across the page), Center, Header, or Footer.
• Privacy. No uploads. The PDF is processed locally and the watermarked copy downloads back to you.
• Cost. Free. No account, no trial, no artificial file limits.

How to watermark a PDF

1. Drop your PDFDrag a PDF into the upload area, or click the drop zone to browse. The tool shows file size and page count after loading.
2. Configure the watermarkPick the Text or Image tab. For text, set the text string, font, size, colour, opacity, position, and rotation. For an image, upload a PNG or JPG and set opacity and scale relative to the page width.
3. Apply and downloadClick Apply Watermark. The new PDF downloads automatically — same pages, with the watermark drawn on top of every one.

What is a PDF watermark?

A watermark is a mark overlaid on a document to indicate its status, ownership, or sensitivity. On physical paper the watermark is pressed into the pulp; in a PDF, it is drawn on top of every page with lower opacity so the underlying content is still legible. Common examples include CONFIDENTIAL stamps on legal documents, DRAFT on unfinished reports, PAID on invoices, a client name across early-draft proofs, or a company logo on every page of a whitepaper.

Text versus image watermarks

Text watermarks are crisp at any zoom level because the text is drawn as vector glyphs, not rasterised pixels. Image watermarks — usually a PNG with transparency — let you stamp documents with a proper logo, signature, or visual badge. This tool supports both: switch tabs depending on what you need.

Position and rotation

The four positions cover the common cases. Diagonal rotates the text across the centre of the page, the classic CONFIDENTIAL stamp — rotation is adjustable from -90° to 90°. Center puts it upright at the page centre. Header and Footer place the watermark at the top or bottom, respectively. Image watermarks always render centred at the given scale and opacity.

Fonts

The three included fonts are the standard PDF base 14: Helvetica (a clean sans-serif), Times Roman (a traditional serif), and Courier (a monospace). Because these fonts are built into every PDF reader, they do not need to be embedded, so the output file stays small and renders identically on every device.

Features of this free PDF watermark tool

• Text or image watermarkUse any string or upload a PNG or JPG logo.
• Standard PDF fontsHelvetica, Times Roman, and Courier — identical in every reader.
• Colour pickerAny colour, from subtle grey to bold red.
• Opacity 5%–100%Ghostly marks or high-contrast stamps — your call.
• Four position presetsDiagonal, Center, Header, Footer.
• Rotation -90° to 90°Fine-grained control for diagonal stamps.
• Image scale 5%–100% of page widthConsistent sizing regardless of source image resolution.
• Applies to every pageOne click, all pages stamped.
• No upload, no serverBuilt on pdf-lib, runs entirely in your browser.
• No watermark on the outputThe only watermark on your PDF is the one you chose.

When to watermark a PDF

• Flag confidential documentsContracts, HR paperwork, board packs — a visible mark sets expectations.
• Mark drafts clearlyStamp early versions with DRAFT so no one circulates them as final.
• Brand client deliverablesAdd your agency or studio logo to every page of a proposal.
• Label paid or void invoicesA PAID or VOID overlay on the invoice PDF keeps records tidy.
• Tag personal informationAdd a "For [name] only" watermark before sharing sensitive scans.
• Protect creative proofsOverlay your name on draft artwork sent to clients before payment.
• Indicate review statusUse APPROVED, REJECTED, or FOR REVIEW on routed documents.
• Add copyright noticesStamp research PDFs or ebooks with an author line or © year.

Privacy: why a browser-based watermarker is safer

The risk with server-side watermark tools

Many free online watermarkers upload your PDF to a remote server, add the mark there, and return a link to download the result. Your PDF sits on their infrastructure for minutes or hours — sometimes longer. That's a poor fit for anything you would actually need to watermark as CONFIDENTIAL.

How this tool stays fully client-side

This watermarker runs 100% in the browser. The pdf-lib library is loaded lazily the first time you drop a file. After that, every operation — reading the PDF, embedding the font, drawing the watermark on each page, and saving the output — happens locally. If you watch the Network tab during Apply Watermark, you will see no outbound document data.

Frequently Asked Questions