What merging does — and what it does not do
Merging joins two or more PDF files end to end. The pages keep their original size, quality and text layer; the tool only changes how they are packaged into one file.
It does not edit content, straighten scans, run OCR, or shrink the result. If you need any of those, do them before or after the merge with a different tool.
Merge PDFs in four steps
The whole job is choosing files, setting the order and downloading one result.
- Open the merge tool and add your PDF files — you can select several at once.
- Drag the files into the order you want them to appear in the final document.
- Start the merge and wait for the combined file to be prepared.
- Download the single PDF and open it to check the first and last pages.
Check the order before you download
The most common mistake is a file in the wrong position. Look at the file list, not just the names: a document called "appendix" usually belongs at the end, but a scanned insert may belong in the middle.
After merging, open the result and check the page count. It should equal the sum of the pages in your source files. If it is lower, a file was skipped or failed to load.
Limits worth knowing
Encrypted or password-protected PDFs usually need to be unlocked before they can be merged; a locked file will either fail or be skipped.
Very large files, or dozens of files at once, can exceed what the browser can hold in memory. If a merge fails, combine in smaller batches and then merge the batches.
Merging also does not create bookmarks, a table of contents, or continuous page numbering across the files.
When merging is the wrong tool
If you only need a few pages from a long document, extract those pages first and merge the results — the output is smaller and easier to check.
If the combined file is too heavy to send, compress it after merging. Compressing before merging gives the same result but takes more steps.