Answers about privacy, file size limits, encrypted PDFs and why there is no compression feature.
Frequently asked questions
Are my files uploaded to a server?
No. There is no server to upload to. The whole toolkit is static files plus a Web Worker running on your device, and you can confirm it by opening your browser’s network panel and watching that no request is made while you work.
Does merging reduce the quality of my pages?
No. Merging, splitting, extracting, deleting, reordering and rotating all copy page content across without re-encoding it. Text stays selectable and images keep their original data.
Why can I not compress a PDF here?
Because the common browser approach is not really compression. It rasterises every page to a JPEG, which destroys selectable text, blurs line art, breaks screen-reader access, and often produces a larger file for text documents. Rather than ship that under a misleading name, the toolkit leaves it out.
What happens with a password-protected PDF?
The tool reports that the document is protected and stops. It does not remove PDF passwords or other access controls. To edit one, open it in a PDF reader with the password, save an unprotected copy, and work from that.
How large a file can I use?
Up to 50 MB per PDF and 30 MB per image. That limit exists because your device does the work: beyond it, a phone is likely to run out of memory mid-operation, which is a worse experience than being told up front.
Does the page order in the merge list matter?
Yes. Files are merged top to bottom in the order you added them. Remove and re-add a file to move it to the end of the list.
Can a watermark stop someone copying my document?
No. A watermark is a visible mark, not an access control. It discourages casual reuse and makes leaks traceable, but anyone who can open the file can still read, copy and print it.
Why was my watermark text rejected?
The 14 fonts built into the PDF format cover Latin characters only. Text in Chinese, Japanese, Korean, Arabic, Hebrew and most emoji cannot be drawn with them. Render the text as a PNG and use the image watermark instead.
Why did my iPhone photos not work?
iPhones save photos as HEIC, which the PDF format cannot embed, so the browser must decode them first. That only works on devices whose operating system supports HEIC. On other platforms, set your iPhone camera to "Most Compatible" to capture JPEG, or convert the files first.
Will my images lose quality when added to a PDF?
JPEGs are embedded exactly as they are, with no re-encoding. PNGs are embedded unchanged too. Only images in other formats are converted, and only very large images are reduced in size — and the tool says so when it happens.
What resolution should I pick for PDF to images?
"Good" suits reading on screen and sharing. Choose "High" or "Very high" for printing or zooming in. Very high on a long document is memory-hungry, so on a phone convert a few pages at a time using "Extract pages" first.
Can I watermark only some pages?
Yes. Both watermark tools take a page specification using the same syntax as the other tools, for example "1" for a cover page or "2-" for everything after it. Leave it empty to mark every page.