Add a watermark to a PDF
Mark every page as a draft, confidential or a copy for one person, without sending the document anywhere.
- Nothing is uploaded
- Works offline after first visit
- Open source
- The limit is your device’s memory (phones hold less)
Stamps text such as CONFIDENTIAL or DRAFT on every page of a PDF, diagonally, repeated or in a corner. It is free, and your files are not uploaded: everything runs in your browser on your device. The limit is your device’s memory (phones hold less)
Done
Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
How it works
- Drop one or more PDFs, or tap to pick them.
- Type the text, such as CONFIDENTIAL or DRAFT, and pick the placement, size, opacity and colour, checking the preview of page 1.
- Download the watermarked PDF. Every page gets the mark, sized to that page.
In your browser, not on a server
pdf-lib (MIT) opens the PDF in your tab. For each page size, the watermark is drawn once on a transparent canvas at about 216 dpi and embedded as a PNG, then placed over every page of that size, following each page’s crop box and rotation. The original page content is not rewritten, so text, links and forms are untouched.
Compared with upload-based tools: Online PDF watermark tools upload the whole document to add a line of text to it, and the documents people watermark are the confidential ones. Here your files are not uploaded, there is no page or file limit, and nothing but your watermark is added.
Verify it yourself. Give the page a short while after one visit to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
Is my PDF uploaded?
No. The PDF is opened, stamped and saved by code running in your browser tab. The documents people watermark are usually the sensitive ones, such as contracts, bank statements, pay slips and scans of IDs, and here they never reach a server.
Can the watermark be removed?
It is added to each page as an image layered over the content, so it cannot be selected and deleted like text in most PDF readers. Someone with a PDF editor can still find and delete the image. For a copy that cannot be cleaned, choose Repeated and then flatten the PDF with the compress tool’s Flatten option, which turns each page into a single picture.
Does it change the rest of the document?
No. Text stays selectable and searchable, links and form fields keep working, and page sizes are unchanged. Only the watermark layer is added on top of each page.
Which placement should I use?
Across the middle is the classic diagonal CONFIDENTIAL or DRAFT stamp. Repeated tiles the text over the whole page, which is the safest for a copy of an ID or a statement you have to send to someone. Corner adds a small, quiet mark, such as a name and date, that does not get in the way of reading.
Does it work on scanned and password-protected PDFs?
Scanned PDFs work like any other. A PDF that only needs a password to change (not to open) is handled automatically. If it asks for a password to open, remove it first with the unlock PDF tool, using the password you know.
What about landscape or mixed-size pages?
Each page gets its own watermark sized to it, so a landscape page or an A3 drawing in the middle of an A4 document is covered the same way, and rotated pages come out the right way up.
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Crop PDF
Cut PDF pages down to what matters: draw the area to keep, or trim the white margins automatically.
Redact PDF
Find a name or number and black it out for good, or draw boxes by hand. The document stays on this device.
Popular conversions
Guides
- How to add a watermark to a PDFStamping "confidential" or "draft" across every page needs either the original document or a tool built for it. Here is how.
- A free Smallpdf alternative with no daily limitSmallpdf's free plan has daily limits. Here is what that means, and a way around it where your files are never uploaded.
- A free iLovePDF alternative with no task limits or adsiLovePDF's free plan works, but with limits on documents, batches and file size. Here is what changes with a tool that never uploads the file at all.