Watermark PDF — Add Logo or Text to Every Page

Watermark a PDF online — for free, with the same controls a designer expects

A watermark on a PDF used to be the kind of thing you needed Acrobat Pro for. You'd open Tools → Edit PDF → Watermark, fiddle with a panel that hadn't changed since 2009, and hope your trial wasn't expiring this week. With GN PDF, the whole job is one drop, three settings, and a download. No upload. No subscription. No surprise watermark from us hiding in the corner.

Watermarking a PDF is something every freelancer, agency, lawyer, school administrator, and small-business owner ends up doing eventually. You have a contract draft that should not be mistaken for the final version, so you stamp DRAFT diagonally across every page. You have a sample portfolio to send a prospective client, so you slip your studio logo into the background at 20% opacity. You are circulating a board report internally and you mark it CONFIDENTIAL in red on the top-right corner. These are real, daily jobs — and the GN PDF watermark tool was built specifically for them.

How to add a watermark to a PDF (text or image), step by step

1. Drop your PDF onto the page (or click "Choose PDF"). The file never leaves your browser.
2. Pick the watermark type. Text — for words like "Draft", "Confidential", "Sample", "Copy of [Client Name]". Image — for your logo, an approval stamp, or a custom design.
3. Tune the controls. Font, size, colour, opacity (5–100%), rotation (-180° to +180°), and position (center, diagonal across the page, tile, or any of the four corners).
4. Choose your page range. All pages, or specific pages like 1-3,5,7-9 for cover sheets only.
5. Decide layering. Tick "Behind page content" if you want existing text to overlay the watermark — the way most legal "Draft" stamps work. Leave it unticked to stamp on top.
6. Live Preview — see exactly how page 1 will look before exporting.
7. Apply & Download. Your watermarked PDF saves straight to your Downloads folder.

The watermark presets we get asked for the most

• Diagonal "CONFIDENTIAL" in red at 35% opacity — the classic compliance look. Set type=Text, text=CONFIDENTIAL, colour=#c0392b, position=diagonal, rotation=-30°.
• Logo bottom-right, 20% opacity, behind content — clean brand signature without obscuring the page. Set type=Image, position=bottom-right, opacity=20%, tick "behind page content".
• "DRAFT" tile, large, light grey at 18% opacity — for circulating versions of a document before final approval. Set type=Text, text=DRAFT, colour=#777, size=140, position=tile.
• "PAID" stamp, top-right, green — for invoices that have cleared. Set type=Text, text=PAID, colour=#1f9d55, position=top-right, size=80, rotation=-15°.
• "COPY" — for certified copies of legal documents — Set type=Text, text=COPY, position=diagonal, opacity=25%.

Why people pick GN PDF for watermarking instead of the alternatives

Most "free" online watermark tools have one of three catches. The first is a file-size limit (5 MB on Smallpdf, 25 MB on iLovePDF unless you sign up). The second is a daily-uses limit. The third — and most embarrassing — is that they apply their own watermark to your output. GN PDF has none of those. It is genuinely free, genuinely unlimited (the only limit is your browser's memory), and it never touches the file with our branding.

Beyond "free", the actual reason most professionals keep coming back is the control panel. Where most free tools give you "pick a colour, type your text, done", GN PDF gives you:

• Fine-grained rotation in 1° steps — useful for matching an existing letterhead.
• Opacity in 1% steps — the difference between a watermark that looks professional and one that looks like a printer error.
• Tile mode — for the strongest possible deterrent against unauthorised reuse.
• "Behind page content" toggle — so the watermark sits under the text the way Adobe's own watermarking does.
• Range selector — watermark only the cover page, only the appendices, or only the middle 20 pages of a 200-page document.

Legal and professional uses for PDF watermarks

A watermark is not just decoration. In legal and corporate contexts, it serves a precise purpose: it disambiguates the status of a document. A version stamped "DRAFT" cannot easily be passed off as final. A "CONFIDENTIAL" stamp puts the recipient on notice. A "COPY" stamp distinguishes a duplicate from an original. A name + date watermark identifies who received which copy, useful for tracing leaks. Used well, watermarks reduce mistakes and create an audit trail. They are not, on their own, a substitute for proper redaction (use our Redact PDF tool for that) or encryption (use Protect PDF).

About this tool — how it works under the hood

The watermarker reads your PDF into memory using pdf-lib, walks each page's content stream, and either prepends (behind) or appends (on top) a fresh content stream containing your watermark. For text, the chosen colour is decomposed into PDF DeviceRGB, opacity is applied via a graphics state dictionary (the same mechanism Acrobat uses), and rotation is applied as a transformation matrix. For images, your PNG/JPEG is embedded once and referenced on every selected page — so a 12-page document with a logo watermark only adds the image bytes once, not twelve times.

Limitations to be aware of

• Encrypted PDFs. If your source PDF is open-password protected, run it through our Unlock PDF tool first.
• Very small fonts. Watermark text below 8pt may be hard to read; we recommend a minimum of 12pt for visibility.
• Embedded fonts. The text watermark uses the three "standard PDF fonts" (Helvetica, Times-Roman, Courier) which every PDF reader has built-in. This keeps the file small. For custom typeface watermarks, save your text as a transparent PNG and use the image mode.

Related — combine watermarking with our other tools

• Watermark + Merge: Merge first using Merge PDF, then watermark the consolidated file in one pass.
• Watermark + Compress: If your watermarked PDF is being emailed, follow up with Compress PDF to keep it under the inbox cap.
• Watermark + Protect: For documents that should be both stamped and locked, watermark first, then password-protect with Protect PDF.