Question 1

How do I merge PDF files online for free?

Accepted Answer

Upload your PDF files using the tool above, drag them to set the order you want, then click "Merge PDFs". The combined PDF downloads to your device in seconds. No sign-up, no email and no payment required — it is completely free.

Question 2

Is there a limit to how many PDFs I can merge?

Accepted Answer

There is no fixed file limit — merging runs entirely in your browser, so the practical limit is your device's memory. Typical documents like forms, reports and presentations merge instantly; very large PDFs (hundreds of MB) may be slow on low-end devices.

Question 3

Are my PDF files uploaded to a server?

Accepted Answer

No. All PDF merging happens entirely in your browser using pdf-lib, a JavaScript library. Your files never leave your device and are never sent to any server. This makes the tool private by design — suitable for sensitive documents.

Question 4

Will the merged PDF have watermarks?

Accepted Answer

No watermarks are added. The merged PDF is a clean document with no branding, watermarks or footers added by ToolKaro. The output is identical in quality to the input PDFs.

Question 5

Can I merge password-protected PDFs?

Accepted Answer

Currently the tool does not support password-protected PDFs. You will need to remove the password protection first (using your PDF reader software) before merging. We plan to add password-protected PDF support in a future update.

Question 6

Does the order of files matter when merging?

Accepted Answer

Yes. The pages in the merged PDF appear in the same order as the files in the upload list. Use the drag handle to rearrange files before clicking "Merge PDFs". The first file's pages appear first, followed by the second file's pages, and so on.

PDF Merger

How to use PDF Merger

Frequently Asked Questions