Add text or image watermarks to every page of your PDF. Control position, opacity, rotation, size, and color. Applied to all pages. Free, no signup, no limits.
Select a PDF to watermark
Drag & drop your PDF here, or click to browse
PDF files only · Up to 100 MB
How it works
No software to install. Works on any device with a modern browser.
Click "Select PDF file" or drag and drop. SupaPDF reads your file securely in the browser.
Choose text or image mode, set position, rotation, opacity, font, and color. Use mosaic to tile the watermark across every page.
Click "Add watermark" and your file is ready in seconds. All original content, links, and fonts are fully preserved.
Why SupaPDF
Trusted by developers and businesses worldwide for reliable, high-quality PDF editing at scale.
Stamp any text (CONFIDENTIAL, DRAFT, your company name) or upload a logo/image. Full control over font, size, color, and rotation.
All uploads use encrypted HTTPS. Your files are permanently deleted from our servers immediately after your download is complete.
Enable mosaic mode to repeat the watermark in a grid pattern across every page - ideal for confidential documents.
Automate watermarking via the add_watermark REST operation. All options - mode, position, rotation, opacity, layer - available as API params.
Developer API
Use the add_watermark operation for text or image watermarks. All positioning, styling, and layer options are available as API parameters.
curl -X POST https://api.supapdf.com/v1/jobs \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"tag": "add-watermark-job",
"tasks": {
"upload-1": { "operation": "import/upload" },
"watermark": {
"operation": "add_watermark",
"input": ["upload-1"],
"mode": "text",
"text": "CONFIDENTIAL",
"vertical_position": "middle",
"horizontal_position": "center",
"rotation": 45,
"transparency": 30,
"font_family": "Helvetica",
"font_size": 40,
"font_color": "#ef4444",
"layer": "above",
"mosaic": false,
"pages": "1,3,5-8"
},
"export-result": { "operation": "export/url", "input": ["watermark"] }
}
}'Operation: add_watermark. Required param: mode: "text" | "image". Key options: transparency (0–100), rotation (0–360), layer ("above"/"below"), mosaic (bool).
FAQ
Everything you need to know about watermarking PDFs with SupaPDF.
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