Merge PDF files
TL;DR: add up to 30 PDF files, drag them into the right order and download one combined PDF. Merging happens in your browser, so your documents are never uploaded anywhere.
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Contracts with their appendices, invoices for the month, chapters of a report from different people: sooner or later everything has to become one PDF. This tool joins the files in the order you set and keeps every page exactly as it was, without converting it to an image.
How to use it
- Add PDF files. Drag up to 30 files onto the box or choose them with the button. For each file you will see the first page and the number of pages.
- Set the order. Drag the rows or use the arrows. The file at the top goes first.
- Merge. Press “Merge PDF”. A 200-page result usually takes a few seconds on an ordinary laptop.
- Download the combined file. To make it lighter, run it through Compress PDF.
What is kept when you merge PDF files
| Element | After merging |
|---|---|
| Text | Kept: you can select, copy and search it |
| Fonts, vector graphics, images | Kept without quality loss |
| Page size and orientation | Kept for each page separately |
| Links to websites | Kept |
| Bookmarks (outline) of the original files | Not carried over |
| Password protection | Protected files cannot be merged: remove the password first |
Pages are copied together with their fonts and images, not printed again, so the merged file looks exactly like the originals and stays as sharp. Its size is roughly the sum of the source files; shared fonts are not deduplicated.
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FAQ
How do I merge PDF files into one?
Add the files, arrange them in the right order with drag and drop or the arrows, press “Merge PDF” and download the result. No sign-up or installation is needed.
Is it safe to merge confidential documents here?
Yes. Merging runs in your browser with the open-source pdf-lib library, and the files are not sent to any server. You can check it in the Network tab of the developer tools: no request contains your documents.
Will the text stay selectable after merging?
Yes. Pages are copied as they are, so the text layer, fonts and vector graphics are kept. You can still search, select and copy text in the merged file.
How many files and pages can I merge?
Up to 30 files, each up to 200 MB. A 200-page result takes a few seconds on an average laptop. Very large documents depend on the memory of your device.
What if a PDF is password-protected?
The tool will tell you which file is protected instead of failing. Open it in a PDF reader, remove the password (or print it to a new PDF) and add it again.
Are bookmarks and form fields kept?
Bookmarks (the outline panel) of the original files are not carried over. Form fields keep their appearance, but may stop being editable in the merged file; fill in forms before merging.
Can I merge PDF files on a phone?
Yes. The page works in mobile Safari and Chrome: choose files from the Files app or downloads, reorder them with the arrows and download the result.