Add Watermark to PDF

Stamp a text watermark like CONFIDENTIAL or DRAFT across every page, in your color and opacity. Free in your browser — no sign-up, no watermarks.

Drop your PDF files here

or click to browse — Select multiple files for batch conversion

pdf

⚡ Instant — conversion starts the moment you add files. No sign-up, no watermarks. Why FileHugger

🔍 How your file is processed
Runs
In your browser on this page
Engine
pdf-lib restructures the document in your browser
Max input
512 MB per file
Your file
Processed in this browser tab — the file is not uploaded. Converted results are kept in this browser's local storage for up to two hours so their matching download page can show them; expired results are removed on the next site visit. Nothing is stored on our servers.
Good to know
Pages are copied as-is — text, links and quality are preserved.

Full security & file-privacy details →

Related converters

PDF → JPGPDF → PNGPDF → WebPPDF → TXTJPG → PDFPNG → PDF

How to watermark a PDF

  1. Click Choose files (or drag & drop) and select one or more PDF files. You can also paste them from your file manager.
  2. Type the watermark text, then set the color, opacity and diagonal or horizontal placement.
  3. Press Add watermark. Processing runs with a live progress indicator.
  4. Open the download page to save your files individually or grab everything as a single ZIP.

Why watermark a PDF?

A visible watermark tells everyone how a document may be used — DRAFT stops premature sign-offs, CONFIDENTIAL discourages forwarding, PAID marks settled invoices. Type any text, choose color, opacity and diagonal or horizontal placement, and it is stamped consistently across every page.

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What this tool preserves — and what it changes

✓ Preserved

  • The underlying pages — the watermark is drawn into the page content on top, nothing is rasterized and text stays selectable
  • The watermark text itself stays out of our records: reports and analytics only ever carry whitelisted settings (opacity, placement style) — never the text you typed

↺ Changed

  • Every page gets your text in fixed 50 pt Helvetica Bold at the color and opacity you choose (10–80%), diagonally at 45° through the page center or horizontally
  • The stamp becomes part of the page content, so every viewer and printer reproduces it — a visible deterrent, not encryption

Known limits & edge cases

  • The built-in Helvetica font only covers Latin-1 (WinAnsi) text — a watermark in Cyrillic, CJK or emoji fails with an encoding error naming the character it cannot write, instead of stamping substitute glyphs
  • Text is capped at 60 characters, and a long string at 50 pt can run past the edges of a small page — short words like DRAFT read best

Engine: pdf-lib restructures the document in your browser. These statements describe the engine as shipped on 2026-10-02 — behaviour changes are recorded in the changelog.

About the formats

What is a PDF file?

PDF is the universal document format: it locks layout, fonts and images so a file looks identical on every device and printer. Scans, invoices, forms, e-books and reports all travel as PDF. Because a PDF is a container rather than an image, turning its pages into JPG or PNG pictures — or bundling pictures into a PDF — are among the most common file tasks there are.

Status and ownership, stamped on every page

A document’s status should be visible on the document, not just in the email around it — forwards lose context, printouts lose everything. A watermark bakes DRAFT, CONFIDENTIAL, SAMPLE or your company name into every page: choose the text, color, opacity and diagonal or horizontal placement, and the marking travels with the file wherever it’s forwarded, saved or printed.

Opacity is the craft: 15–30% reads clearly without fighting the content — the goal is a label, not a barricade. Diagonal center placement is the strongest deterrent for drafts and review copies, since cropping can’t remove it; horizontal suits subtler branding. Watermark after the content is final and before it leaves your hands, and keep an unmarked original for the day the document graduates from draft.

Frequently asked questions

Is this Add Watermark to PDF tool free?

Yes — completely free, with no sign-up, no watermarks and no daily quota. Processing happens in this browser, so the practical limit is the memory available on your device.

Can I process multiple PDF files at once?

Yes. Add as many files as you like — each one is processed in sequence with its own progress status, and you can download the results individually or all together as a ZIP archive.

Does editing re-compress my PDF or reduce its quality?

No. Pages are copied at the object level — text, fonts, images and vector content are carried over as-is, without re-rendering. The output keeps the same sharpness and searchable text as the original.

Can the watermark be removed later?

The watermark is drawn into the page content, so viewers and printers reproduce it everywhere. Like any visible watermark it is a deterrent, not encryption — determined editing tools can still alter pages.

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