Frequently asked questions
Questions that come up across the tools. Each tool page also answers the ones specific to it.
Is pdfsmerger.com free?
Yes, every tool is free with no account, no subscription and no watermark on anything you download. There is no paid tier holding back features.
Do I need to create an account?
No. There is no signup, and we do not ask for an email address. Upload a file, use the tool, download the result.
What happens to my files?
They are uploaded over an encrypted connection, processed, and deleted from storage shortly afterwards. We do not open, read or review file contents, and nothing is retained beyond the session.
Is it safe for confidential documents?
Files are encrypted in transit and removed after processing, which suits ordinary sensitive material like statements or scanned ID. For documents under a strict legal or regulatory handling obligation, use software that runs entirely on your own machine — that is true of any online tool, not just this one.
Is there a file size limit?
Individual files are limited to 20MB and a single request to 100MB. Larger documents are usually best split first, then processed in parts.
Which image formats are supported?
JPG, PNG, WebP, GIF and BMP for image-to-PDF conversion. The compression tools accept JPG and PNG. Output from the compressors is always JPEG, which is how the size reduction is achieved.
Do the tools work on a phone?
Yes. Everything runs in the browser on iPhone, Android, tablets and desktops, with nothing to install.
Why did my PDF barely get smaller when I compressed it?
Because compression works on the images inside a document, and a text-heavy PDF has almost none. Scans and image-rich reports see large reductions; a text contract has nothing to reduce.
Why does merging fail on some files?
Almost always because one of them is password-protected. An encrypted PDF cannot be read without its password, so the merge stops rather than silently dropping pages. Unlock it first, then merge the unlocked copy.
Can you recover a PDF password I have forgotten?
No. The unlock tool removes protection from a document you can already open — it needs the existing password. Recovering an unknown password is not something we do.
Will converting a PDF to Word give me an editable copy of my layout?
You get the text as editable text, plus an image of each page for reference. Columns, tables and precise positioning are not rebuilt, because a PDF stores where marks sit on a page rather than the structure behind them.
Do you add watermarks?
No. Nothing is added to any file you download.
Still stuck? The tool pages go into more detail on what each one does, including the cases where a tool is the wrong choice.