Add a watermark to a PDF
Stamp your own text — like CONFIDENTIAL, DRAFT or a name — diagonally across every page of a PDF. Choose the wording and how strong the watermark looks, then download. Everything runs in your browser, so your document is never uploaded.
How to use Watermark PDF
- 1
Add your PDF
Drag a PDF into the drop area, or click to choose one from your device.
- 2
Type your watermark
Enter the text you want — for example CONFIDENTIAL, DRAFT or your name.
- 3
Set the opacity
Adjust how strong or subtle the watermark appears with the opacity control.
- 4
Apply and download
Click apply and save the watermarked PDF. Your file is never uploaded anywhere.
Mark a document as yours or as a draft
A watermark is a simple, powerful way to communicate something about a document at a glance: that it is confidential, that it is only a draft, that it belongs to you, or that it is a sample not meant for distribution. By laying semi-transparent text diagonally across every page, a watermark stays visible no matter how the document is viewed, shared or printed, without obscuring the underlying content. In1 lets you type whatever text you want — CONFIDENTIAL, DRAFT, COPY, a company name, a person's name, a date — and stamps it across the entire PDF in one step. It is the fastest way to signal intent before you send a file out: a draft contract that should not be acted on yet, an internal report that must not circulate, or a proof you are sharing for review. The message rides along with the document, so anyone who opens it understands its status immediately. Because the watermark sits over the content rather than replacing it, the document remains fully usable — readable, printable and shareable — while carrying its label everywhere it goes. That combination of clear signalling and untouched content is exactly why a diagonal text watermark has become the standard way to mark drafts, copies and confidential material.
Control the text and how strong it looks
A watermark has to strike a balance: visible enough to register, but faint enough that the document underneath stays readable. In1 puts that balance in your hands. You choose the exact text, and an opacity control lets you set how bold or subtle the stamp appears — a heavier setting for an unmistakable CONFIDENTIAL warning, or a lighter one for a gentle DRAFT or ownership mark that does not get in the way of reading. The watermark is sized and angled to span each page diagonally, which is the classic, professional look and the hardest to crop out or ignore. Because you can adjust the wording and strength and re-run instantly, it is easy to preview different options and land on a watermark that does its job without overwhelming the content beneath it.
Applied to every page automatically
A watermark is only effective if it is on every page — a confidential notice that appears on page one but not page five is easy to miss or misuse. That is why In1 applies your watermark to all pages of the document at once, consistently, so the message is unmissable throughout. There is no need to place it page by page or worry that some pages slipped through. The text is drawn directly into the PDF as part of each page, so it travels with the file: it shows up when the document is opened in any reader, when it is shared, and when it is printed. Whether the PDF has a single page or hundreds, the watermark is stamped uniformly across all of them in one quick operation, giving the whole document the same clear status from the first page to the last.
Private and free — nothing is uploaded
The documents people watermark are very often the sensitive ones — confidential reports, draft contracts, proprietary designs, paperwork being shared for limited review. Uploading such a file to an online service to stamp it would undercut the very confidentiality the watermark is meant to assert. In1 adds the watermark entirely in your browser, so your document is read into memory, stamped on your own device, and handed straight back to you as a download — nothing is uploaded, stored or logged, and there is no account to create. Because the work is local there is no file-size cap from a pricing plan and, of course, no unwanted watermark of ours added on top of yours. You get the convenience of an online tool with the privacy of an offline one, which is exactly what you want when the whole point is to control how a private document is handled.
Who adds watermarks to PDFs?
The use cases span work and personal life. Businesses stamp CONFIDENTIAL or INTERNAL on reports and plans before circulating them, and DRAFT on documents that are not final. Freelancers and agencies watermark proofs and samples — designs, photos compiled into a PDF, written deliverables — so previews cannot be used without payment. Legal and finance teams mark copies, drafts and privileged documents. Photographers and creators protect portfolios shared as PDFs with their name. Students and researchers sometimes mark drafts of a thesis or paper. Anyone sending a document for review who wants to make its status unmistakable reaches for a watermark. In every case the goal is the same: lay a clear, consistent message across the pages of a PDF to signal ownership or status — quickly, privately and for free, without installing specialized software or exposing the file to a server. It also slots neatly into a wider PDF workflow: watermark a draft before circulating it for review, then later remove the draft version and share a clean final, or combine watermarking with compressing and splitting depending on what each recipient needs — all handled locally in the browser.
Higher limits, batch processing and an API are on the way. Want early access?