Add Watermark to PDF Online Free

Protect documents with CONFIDENTIAL, DRAFT, or custom watermarks

No signup • No watermark • 100% Private • Completely Free

See the Result

Before

Unprotected document

→

After

Watermarked with "CONFIDENTIAL"

Add Watermark to PDF

Protect your documents with text watermarks

Upload Your PDF

Select a PDF document to add watermarks

Why Use Our Free PDF Watermark Tool?

PDF Watermark Privacy

Add watermarks to PDFs using pdf-lib locally. Your documents and watermark text stay on your device during processing.

Custom Watermark Control

Add text watermarks with opacity, positioning, rotation, and color control. Perfect for protecting documents, marking drafts, or adding copyright notices.

Unlimited PDF Watermarking

Watermark entire document libraries without restrictions. No limits on page count, file size, or number of watermarked PDFs per day.

Direct Watermark Access

Start watermarking PDFs immediately. No account creation, no email verification - just upload and protect.

How to Add Watermark to PDF

Upload Your PDF Document

Select the PDF file you want to add a watermark to.

Customize Watermark Settings

Choose text (CONFIDENTIAL, DRAFT, etc.), adjust opacity, rotation, and color.

Download Protected PDF

Click "Add Watermark" and download your watermarked document instantly.

Frequently Asked Questions

Is this PDF watermark tool really free?

Yes, completely free. No hidden fees, no subscriptions, no credit card required.

Do I need to create an account?

No. Start immediately without signup or email verification.

Are my PDFs uploaded to your servers?

No. All processing happens in your browser. Files never leave your device.

Can I add a watermark to specific pages only?

Yes. Choose "Specific pages" and enter page numbers like "1,3,5-7" to watermark only those pages.

Can I remove the watermark later?

No. Once watermarked and saved, the text is permanently embedded in the PDF. Keep a backup of your original file.

What text can I use as a watermark?

Any text you want. Common options include CONFIDENTIAL, DRAFT, COPY, or your company name.

Will watermarking increase PDF file size?

Slightly. Text watermarks add minimal size increase, typically less than 1% of the original file size.

💡Pro Tips: PDF Watermarking Best Practices

•"CONFIDENTIAL" in red at 30% opacity is the legal industry standard
•Diagonal watermarks (45°) are harder to crop out than horizontal ones
•Use gray color for a subtle background watermark that doesn't obscure text
•"DRAFT" watermarks help track document versions in review cycles
•Once watermarked and saved, the text is permanently embedded in the PDF

How the PDF Watermark works

The watermark is drawn into the PDF itself with pdf-lib, using the built-in Helvetica Bold font. You control the text (default “CONFIDENTIAL”), font size (default 60 pt), colour, opacity (default 30%) and angle (default 45°), and you can stamp every page or only selected pages.

Because the watermark is real vector text added to each page’s content, it stays sharp at any zoom level and prints correctly. A live preview of the first page is rendered with pdf.js so you can check the result before downloading.

Example: marking a contract as a draft

Type DRAFT, keep 45°, set opacity to 20% and choose grey. On a standard A4 page (595 × 842 points) a 60 pt diagonal watermark crosses the centre of the page without hiding the text underneath. Enter “1-3” in page selection to stamp only the first three pages.

Tips for the best result

Use 15–30% opacity so the document stays readable.
Red or grey text works best on white pages; avoid black, which competes with the body text.
Keep the original unwatermarked PDF; once flattened and shared, a watermark is part of the page.

Limitations to know

Built-in PDF fonts cover Latin characters only; text in Urdu, Arabic, Chinese and other scripts cannot be drawn with Helvetica.
Password-protected or encrypted PDFs must be unlocked before they can be modified.
A text watermark can be removed by someone with a PDF editor; it deters copying but is not a security feature.

Troubleshooting

Error when loading the PDF: The file may be encrypted or damaged. Open it in a PDF reader, “Print to PDF” a new copy and try again.
Watermark is off-centre on some pages: Pages with different sizes or rotations are handled individually; check the preview on those pages and adjust the font size.

PDF Watermark: common questions

Will the watermark appear when printing?

Yes. It is part of each page’s content, not an annotation, so it prints and shows in every PDF reader.

Can I watermark only some pages?

Yes. Turn off “apply to all pages” and enter page numbers or ranges such as 1,3,5-7.

Does it reduce PDF quality?

No. Existing page content is not re-compressed; only the watermark text is added.