Add a Watermark to a PDF Free, Including Scanned PDFs
Free Tool Tests • Add a Watermark to a PDF Free, Including Scanned PDFs
💡 Summary
Add text or a logo to a PDF with the free watermark tool. In our test, it produced a watermarked PDF from a scanned, image-only file.
Key Metrics & Specifications
| Tool | Free Watermark PDF: Add Text or a Logo to Every Page |
| Tested | 2026-11-06 · Chromium (desktop) · free version |
| Test cases passed | 14 of 14 |
| Tool page | https://avaloncompany.ai/tools/watermark-pdf/ |
What we ran through the tool
14 of 14 cases behaved correctly · 2026-11-06 · Chromium (desktop) · free version
| Input | Type | What the tool did |
|---|---|---|
| a typical file | Typical file | PDF file, 3 pages “32.0 KB · Watermark on 3 pages” |
| a very long file name | Tricky file | PDF file, 3 pages “32.0 KB · Watermark on 3 pages” |
| a file name with extra spaces and an emoji | Tricky file | PDF file, 3 pages “32.0 KB · Watermark on 3 pages” |
| a file name with Korean and Japanese characters | Tricky file | PDF file, 3 pages “32.0 KB · Watermark on 3 pages” |
| a 1-byte PDF file | Tricky file | Not processed “pdf_1byte.pdf is not really a PDF: its contents are in a different format, so it was not added.” |
| a password-protected PDF | Tricky file | Not processed “This PDF is locked. Remove the password with the unlock PDF tool first, then watermark the unlocked copy.” |
| a JPEG file renamed to look like a PDF | Tricky file | Not processed “pdf_fake.pdf is not really a PDF: its contents are in a different format, so it was not added.” |
| a PDF with pages of different sizes | Tricky file | PDF file, 3 pages “32.0 KB · Watermark on 3 pages” |
| a PDF with Korean, Japanese, Chinese, Arabic, Hindi, Thai and Russian text | Tricky file | PDF file, 2 pages “71.5 KB · Watermark on 2 pages” |
| a scanned, image-only PDF | Tricky file | PDF file, 1 page “54.0 KB · Watermark on 1 page” |
| a cut-off (truncated) PDF file | Tricky file | Not processed “This file is not a valid PDF or it is damaged.” |
| an empty (0-byte) PDF file | Tricky file | Not processed “pdf_zero.pdf is empty (0 bytes), so it was not added.” |
| a batch 1 MB over the free size limit | Free limit | Not processed “pdf_mb_101.pdf was not added: the limit is 100 MB.” |
| 2 files (one over the free limit) | Free limit | Not processed “The free version watermarks one PDF at a time, so only the first one you chose was used.” |
“Behaved correctly” means the tool produced a valid output file we reopened and checked, or refused the input with a clear message. Open the tool.
Try it on your own file
The same free tool we tested above. No sign-up.
Internal link to avaloncompany.ai.
How to add a watermark
Open the free tool at https://avaloncompany.ai/tools/watermark-pdf/ and drop in your PDF.
Type your watermark text or choose Image and select a PNG, JPG, or WebP logo. Pick the position, size, and opacity.
Leave Pages empty to watermark every page. To mark selected pages, enter a page number or range, such as 1 or 2-5. Press Add watermark.
What we tested
On 2026-11-06, we ran 14 test cases in desktop Chromium using the free version. All 14 passed.
The cases included a typical PDF, unusual file names, different page sizes, multilingual text, a scanned PDF, invalid or damaged files, and free-version limits.
What happened with difficult files
The tool produced PDFs for the scanned file, the file with different page sizes, and the file containing Korean, Japanese, Chinese, Arabic, Hindi, Thai, and Russian text.
The password-protected file produced no PDF. The tool said: "This PDF is locked. Remove the password with the unlock PDF tool first, then watermark the unlocked copy."
The cut-off file also produced no PDF. The tool reported: "This file is not a valid PDF or it is damaged." Empty files and files whose contents were not PDF format were not added.
Free limits and when to choose another approach
The free version watermarks one PDF at a time. In the size-limit test, the tool reported a 100 MB limit. When we chose 2 files, it said only the first was used.
A watermark can be removed with PDF editing software. For private details that must not be seen at all, the tool page recommends using the free redact PDF tool.
We re-run these tests when the tool changes. Results describe this tool on the date shown.
Frequently Asked Questions (FAQ)
Q. Can I use a logo as a watermark?
Yes. Choose Image and select a PNG, JPG, or WebP file. The tool page recommends a PNG with a transparent background.
Q. Can I watermark only selected pages?
Yes. Enter the pages under Pages, such as 1 or 2-5. Leave the field empty to watermark every page.
Q. Is my PDF uploaded to a server?
According to the tool page, the watermark is added in your browser on your own device, and nothing is sent to the tool's servers.
Try it on your own file
The same free tool we tested above. No sign-up.
Internal link to avaloncompany.ai.