03 / HOW TO MERGE PDFS
How to merge PDFs
Select the PDF files you want to combine. You can choose several files at once, and each one can be up to 50 MB and 500 pages. The tool checks these limits right in your browser before starting.
Files are merged in the order they appear in the file list. The list shows each selected file with a Remove button, so you can take out any file you added by mistake. There is no drag-and-drop reordering and no page thumbnails. To change the order, remove a file and add it again in the right position.
The tool accepts between 2 and 20 PDFs in a single merge. If you select 21 files, the merge is refused. There is also a total size cap of about 150 MB across all chosen files, because the work happens in your browser tab and a phone cannot hold much more. Files beyond that cap are left out of the list, and the page tells you so.
04 / WHAT HAPPENS TO YO
What happens to your files
This tool is entirely client-side. The PDF code runs inside your browser tab, and your files are never uploaded to a server. Because nothing is uploaded, nothing is stored. If you close the tab, the working copy is discarded.
There are no settings to change. The tool simply merges the whole of each selected PDF, in the order you provided. There is no page picking, so you cannot choose a subset of pages from a file. Every page of every PDF you include will end up in the merged output.
05 / WHAT THE TOOL CANN
What the tool cannot do
This tool is for merging whole PDFs only. It does not offer any way to reorder pages within the output, trim pages from one file before merging, or combine files by dragging them into a desired sequence. If you need those capabilities, you will need a more full-featured PDF editor.
The tool enforces a strict limit of 20 files per merge. If you select 21 PDFs, the merge will not run. Also, the total size of all files together cannot exceed about 150 MB. If you go over, some files are left out and you will see a message explaining that.
There is no progress percentage shown while the merge runs. The tool works in your browser tab, and you simply wait for it to finish. Larger files may take longer, but you will not see a numeric progress indicator.
06 / WHEN THE RESULT LO
When the result looks wrong
Because files merge in the order they appear in the list, the most common cause of a wrong output order is the selection order. If the merged PDF's pages are not in the order you expected, check the list order and re-add the files in the correct sequence.
Another possibility is that a source file itself had pages in an odd order. The tool includes every page of every file exactly as it exists in the original PDF. If a source file is missing pages or appears blank, the problem likely lies in that original file, not in the merge process.
Also, because the tool cannot preview pages, you may not notice that a file contains unwanted pages until you open the merged result. If that happens, edit the original PDF to remove those pages first, then merge again.
07 / BROWSER AND FILE C
Browser and file considerations
The merge happens in your browser, so the tool relies on your device's memory and processing power. The 150 MB total limit and the 50 MB per-file limit are in place to keep the process reliable, especially on phones. If you are on a low-memory device, working with fewer or smaller files may be necessary.
You do not need an internet connection for the files themselves, but the page itself must load first. Once the tool is open, your files are processed locally. Closing the tab at any time aborts the process and discards the working copy.
The output is a standard PDF. It will not be encrypted or password-protected by this tool; it simply concatenates the page streams of the source files.
FAQ
Common questions
Will merging PDFs reduce quality?
No. The tool combines the full content of each PDF without recompressing images or altering text. The output should match the quality of your source files exactly. If you see lower quality, check the original PDFs—the issue is likely there.
Can I merge more than 20 PDFs?
No. The tool accepts between 2 and 20 PDFs in one merge. If you select 21 files, the merge is refused. You can split your files into batches of 20 or fewer and then merge the resulting PDFs together in another pass, if needed.
How do I change the order of files after I've added them?
The tool has no reorder controls. The merge order is the order in which files appear in the list. To change the order, use the Remove button on each file you need to move, then add them again in the correct sequence.
Are my files uploaded to a server?
No. This tool runs entirely in your browser tab. The PDF files are never uploaded, so nothing is stored on a server. If you close the tab, the working copy is discarded.
What does 'some files were left out' mean?
The tool enforces a total size cap of about 150 MB for all selected files combined. If you go over that, the extra files beyond the cap are left out of the list, and you'll see a message explaining that. Remove some files to reduce the total size and try again.
Why is there no progress bar?
This tool does not show a percentage while it works. The merge happens entirely in your browser, and you just wait for the process to complete. Large files may take a while, but the tool is still working.