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PDF // free tool

Add a text watermark to every page of a PDF.
Customisable.

Last reviewed 2026-06-17

Summary

Add 'CONFIDENTIAL', 'DRAFT', your company name, or any custom text as a diagonal watermark on every page. Pick colour, opacity, font size.

  • Custom text: any word or phrase.
  • Colour picker, opacity slider, font-size control.
  • Applied to every page as diagonal stamp.
  • Free up to 20 pages. Pro removes the limit.
Run it
Click or drag a PDF here
Free: PDFs up to 20 pages
Free tier: PDFs up to 20 pages, Nuvenar watermark added
Tools Pro: unlimited page count, no Nuvenar watermark.
Free outputs include a Nuvenar watermark on every page. Pro removes it.
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What the number means

What is the Nuvenar Watermark PDF tool?

Nuvenar Watermark PDF is a free, browser-side tool that adds a diagonal text watermark to every page of a PDF. Customise the text, colour, opacity, font size, and rotation. It uses the open-source pdf-lib library running in your browser, so your file never reaches a server. Common uses: marking DRAFT, CONFIDENTIAL, or your company name across proposals, contracts, and sample deliverables.

When to use Watermark PDF

  • Marking drafts: so a printed or forwarded copy is unmistakably not the final version.
  • Branding sample deliverables: proposals, design mockups, sample chapters that need to be clearly attributable if they leave the original recipient.
  • Confidentiality stamping: CONFIDENTIAL or INTERNAL ONLY across board packs, M&A documents, and HR files.
  • Copy control: COPY 1 OF 5 or per-recipient initials to track leak source.
  • Pre-publication review: NOT FOR DISTRIBUTION on documents in legal review.

How Watermark PDF works

The tool loads your PDF with pdf-lib, iterates over each page, sets the graphics state to the chosen opacity, draws your watermark text using Helvetica at the requested rotation and size, and serialises the result. The watermark becomes part of the page content stream. It is visible in every viewer, prints exactly as displayed, and is selectable text rather than an image (so it is searchable in the output).

Picking sensible watermark defaults

Most professional watermarks sit at 20% to 35% opacity so the underlying text remains readable. Diagonal placement around -30 degrees reads naturally and avoids competing with horizontal headers and footers. Font sizes between 50 and 80 points fill an A4 page without dwarfing the content. Colour: muted reds and oranges read as warnings, grey reads as neutral branding, blue reads as institutional.

Watermark PDF vs alternatives

Functionality is broadly comparable across the major UK-relevant tools. The differentiators are privacy (browser-side vs upload), daily-task caps on free, and subscription price.

ToolBrowser-sideWatermark on freeFree tier limitPaid price
Nuvenar Watermark PDFYesSmall Nuvenar mark on freeUp to 20 pages£9/mo unlimited
SmallpdfNoNo watermark, 2 tasks/day2 watermark jobs/day€9/mo
iLovePDFNoNo watermarkFree, 25 MB upload€6/mo
Adobe Acrobat OnlineNoNo watermarkPro feature only£15.17/mo + VAT
PDF24 OnlineNoNo watermarkFree, ad-supportedFree online

Privacy and security

Watermarking is most often applied to the most sensitive documents (drafts, board packs, M&A materials, employee contracts). Browser-side processing means none of that reaches a third-party server. No deletion-policy promise to verify, no data-processing record needed for UK GDPR.

Common use cases by profession

  • Consultants: DRAFT across proposal versions during review, company name on portfolio samples.
  • Solicitors: PRIVILEGED AND CONFIDENTIAL on advice memos, matter number on every page for case-file tracking.
  • Accountants: DRAFT on accounts pending sign-off, firm name on management-pack samples.
  • Aesthetics and clinic operators: clinic branding on patient-facing treatment plans, INTERNAL on staff SOPs.
  • HR teams: CONFIDENTIAL on disciplinary and grievance documentation.
  • Designers and agencies: PREVIEW or SAMPLE on mockups sent before payment.

What is included free vs Tools Pro

Free: up to 20 pages, full control over text, colour, opacity, font size, rotation, with a small additional Nuvenar marker on the output. Tools Pro at £9/mo: unlimited pages, no Nuvenar marker, priority support, plus access to every other Nuvenar PDF tool (merge, split, compress, rotate, page numbers) and 25+ business calculators.

Frequently misunderstood things about PDF watermarking

  • Myth: a watermark prevents copying. Reality: it is a visible deterrent, not encryption. Combine with passwords and access control if you need real protection.
  • Myth: watermarks are images. Reality: our watermarks are real PDF text with transparency. Selectable, searchable, accessible.
  • Myth: watermarks slow down PDF opening. Reality: a text watermark adds negligible file size and zero rendering overhead.
  • Myth: the recipient cannot remove a watermark. Reality: a determined recipient with Acrobat Pro can edit it out. Watermarks deter casual leaks, not motivated ones.
FAQ

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

Drop your PDF into the tool above, type the watermark text (e.g. CONFIDENTIAL, DRAFT, your company name), tune the colour, opacity, font size, and rotation, then click Apply. The watermarked PDF downloads in seconds. Free is up to 20 pages, Tools Pro at £9/mo removes the cap and the small Nuvenar marker.

Is this PDF watermark tool free?

Yes. Free tier handles PDFs up to 20 pages. Free output carries both your custom watermark and a small Nuvenar watermark. Tools Pro at £9/mo removes the Nuvenar watermark and the page cap. Smallpdf charges €9/mo, iLovePDF €6/mo, and Adobe Acrobat Pro £15.17/mo plus VAT for comparable tools.

Are my PDFs uploaded when I add a watermark?

No. Watermarking runs entirely in your browser using the open-source pdf-lib library. Your file never leaves your device. Safe for confidential documents under UK GDPR.

Can I change the watermark text?

Yes. Enter any text. Common choices: CONFIDENTIAL, DRAFT, INTERNAL ONLY, your company name, a client matter number, COPY, NOT FOR DISTRIBUTION, or a date.

What colour, opacity, and size controls are available for the watermark?

A standard hex colour picker, opacity from 10% to 80%, font size from 30 to 120 points, and rotation from -45 to +45 degrees. The default settings (orange, 25% opacity, 60 pt, -30 degrees) are tuned for visibility without obscuring content.

Will the watermark cover the page content underneath?

It overlays diagonally across the centre of every page at the opacity you choose. The default 25% opacity keeps text readable underneath. Increase opacity if the watermark needs to dominate (e.g. DRAFT), reduce it if subtle branding is enough.

Can the watermark be removed by the recipient?

Technically yes, with effort. A determined recipient can re-render the PDF to images and back, or edit it in a paid PDF editor. The watermark is a visible deterrent and audit signal, not encryption. For real protection, combine watermarking with a password and access controls in your document-management system.

Why is there a second small watermark from Nuvenar on free outputs?

That is the free-tier marker. It is intentionally visible so we can keep the rest of the tool free for everyone. Tools Pro at £9/mo removes it, plus removes caps on every other Nuvenar PDF tool.

Can I add a logo image as a watermark instead of text?

Not yet. The current tool supports text watermarks only. Image-watermark support is on the roadmap. For now, render your logo as text (your firm name) or use Adobe Acrobat Pro for image watermarks.

Can I watermark a password-protected PDF?

No. Remove the password first using Preview on macOS (File, Export, untick encryption), Adobe Reader, or a free unlocker. The pdf-lib library requires unlocked files.

How is this different from Smallpdf, iLovePDF, Adobe Online, or PDF24?

Smallpdf, iLovePDF, Adobe Online, and PDF24 web upload your PDF before watermarking. Nuvenar processes everything in the browser. Output is comparable; the differentiators are privacy, no daily-task cap, and price. Adobe is the only one with image-watermark support out of the box.

Can I add a different watermark to each page?

Not in this version. The same watermark is applied to every page. For per-page watermarking, split with our split tool first, watermark each section, then merge.

Will the watermark be visible when the PDF is printed?

Yes. The watermark is part of the page content stream, so it prints exactly as it displays. If you do not want it on print, use a separate copy of the source document.

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Want the Nuvenar marker gone?

Tools Pro at £9/mo removes the free-tier Nuvenar marker, lifts the 20-page cap, and unlocks every other PDF tool plus 25+ business calculators.

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