Watermark PDF adds a visible text or image watermark to the pages you choose and downloads a new copy of the document. Use it to mark a draft confidential, add a company name to a proposal, or put a logo on a handout. Everything happens in your browser, so the file never leaves your device.
How to watermark a PDF
- Drop your PDF onto the tool or click Choose file.
- Choose Text or Image.
- For text, type the words and choose a font, size, colour, opacity, angle and position. For an image, upload a PNG or JPG and set its size, opacity, angle and position.
- Leave the page box blank to watermark every page, or type a selection such as
1-3, 5. Page numbers start at 1, and a range such as8-runs to the last page. - Check the preview of the first selected page. It updates as you change the settings.
- Click Watermark N pages, then download the new
<original-name>-watermarked.pdf. Your original file is not changed.
Text watermarks vs image watermarks
Text is quickest for words such as DRAFT, CONFIDENTIAL, SAMPLE, a client name or a date. The three fonts are Helvetica, Times Roman and Courier. Standard PDF fonts keep text sharp and add little to the file size. They cover common Latin letters, numbers and punctuation, but not every alphabet or symbol. For a brand typeface, a non-Latin script or special characters, prepare the wording as a transparent PNG and use an image watermark instead.
An image watermark suits a logo or company stamp. PNG transparency is preserved, so a logo sits over the page without a white box around it. JPG images work too, though they have a solid background unless the image itself is white. The image data is embedded once even when the mark is repeated across several pages.
Opacity, angle and position
Opacity controls how strongly the mark shows. Around 20–30% is a good starting point for a confidentiality mark. Too low a value can disappear on a pale background or a low-quality printer; too high a value can obscure the content underneath.
The angle slider runs from -90° to 90°. Positive angles tilt upwards to the right, and 45° gives the familiar diagonal watermark. Zero is horizontal, which works well for a header or footer, and negative angles tilt the other way. The same setting applies to an image.
Position offers centre, the four corners, top centre, bottom centre and tiled. Corner marks keep a small margin from the edge. The tool reads each page's rotation setting as well as its size, so a top-left mark stays in the top-left corner even when the page is stored sideways or upside down.
Tiled watermarks
Tiled mode repeats the watermark across the page in a diagonal grid and clips it at the page edges. It is useful when a single centred mark would be easy to crop away, or when every part of the page should carry a reminder that the document is a draft or sample.
The spacing grows when the mark is small, so a page never fills with hundreds of tiny copies. Use 20–30% opacity at about 45°; if the page becomes hard to read, lower the opacity rather than enlarging the tiles.
Quality and what is preserved
The tool leaves the pages as they are and adds a new content layer. Nothing is re-rendered or re-compressed. Original text stays selectable and searchable, images keep their resolution, and page sizes, orientation and existing rotation settings are kept.
Text watermarks add only a small amount of data. Image watermarks add the embedded image plus a reference each time the image is drawn, so a tiled logo can increase the file size a little more than a single corner logo. The download is a separate file; the PDF on your disk stays untouched.
Limitations
A watermark is a visual mark, not copy protection. Anyone with a PDF editor can cover it, crop the page or remove the added layer, and the underlying text and images can still be extracted. It is not DRM, encryption or proof of ownership, does not stop screenshots or printing, and is not a digital signature.
Password-protected PDFs cannot be opened here. Save an unprotected copy from your PDF reader, then watermark that. Scanned pages work normally because the mark is drawn on top, but the tool does not perform OCR, so text in a scan remains an image rather than searchable text. Very large PDFs are best handled on a computer because the whole document is held in the browser's memory.
Common uses
- Marking drafts, proposals and reports as DRAFT or CONFIDENTIAL.
- Putting a company name, website or logo on quotations and handouts.
- Adding a date or reference number to pages that may be printed and filed.
- Labelling review copies and sample pages before sharing them outside an organisation.
- Branding a PDF that will be printed for an event.
Privacy
The PDF and any watermark image are read by your browser and processed locally. Nothing is uploaded to Lembog or another server, no account is needed, and the tool adds no watermark of its own. The document stays in your browser's memory until you download it or close the tab, which makes the tool suitable for contracts and internal reports.
Related PDF tools
- To straighten sideways pages before watermarking, use Rotate PDF.
- To reorder or delete pages, use Organize PDF.
- To add page numbers at the same time, use Add Page Numbers to PDF.
- To trim the page margins before watermarking, use Crop PDF.
- To combine several documents first, use Merge PDF.
- To break a watermarked document into separate files, use Split PDF.
Watermark PDF FAQ
Is my PDF uploaded anywhere?
No. The file is opened, previewed and saved by your own browser. It is never sent to Lembog or any other server, so the tool is safe for private documents.
Does watermarking change my original PDF?
No. The tool creates a new PDF in the browser and leaves the file on your disk untouched. You can keep both copies or delete either one.
Can I watermark only some pages?
Yes. Leave the page box blank to mark every page, or type a range such as 1-3, 7. This is useful when a cover or signature page should stay clean.
Can I use a company logo as a watermark?
Yes. A PNG with a transparent background gives the cleanest result. Set its size as a page-width percentage and choose a position. JPGs work but may show a solid background.
Will a watermark stop people copying or editing the document?
No. A visible watermark is a deterrent and a labelling tool, not copy protection. It can be removed or covered with PDF editing software, and it does not prevent text extraction, screenshots or printing. Use encryption or access controls if you need technical restrictions.
Why does the watermark look slightly different in the preview?
The preview is an approximation drawn by the browser. The saved PDF uses the font's own measurements and the page's exact dimensions, so spacing and position can differ by a small amount. Check the downloaded file before sending it on.
Can I remove a watermark later?
This tool does not remove watermarks, and removing an overlay cleanly usually means editing the PDF in another application. Keep the original file as the simplest starting point if you need a version without the mark.
Does watermarking work on scanned PDFs?
Yes. A scan is an image on a page, and the watermark is drawn over it. The scan's text does not become searchable, however, because this tool does not run OCR.