Choose two or more PDFs, put them in the order you want, and download one combined file. The pages are joined as they are, so a mix of A4 and Letter pages stays a mix. The limits are 20 files per merge and 20 MB per file, and a file protected by a password cannot be merged. The result is one plain PDF; this is not a tool for rearranging individual pages, so use Extract PDF Pages first if you only need some of them.
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Accepts PDF · up to 20 MB each
Files will be merged in this order:
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Your file is processed on our server and deleted automatically afterward — see the privacy note below.
Overview
About Merge PDF
Order and page sizes
Files are joined in the order they are listed, and the controls let you move a file up or down before you merge. We merged a 3-page A4 file, a 2-page Letter file and a 4-page mixed file: the result had 9 pages in exactly that order, and every page kept the size it had, A4, Letter and A3 included. Nothing is resized to match, so a merged file can have pages of different sizes. If that matters for printing, the PDF Page Size Analyzer lists the size of every page.
Limits and what gets refused
| Situation | Result |
|---|---|
| One file | Refused: "Choose at least 2 PDF files to merge." |
| 20 files | Merged (our 20 two-page files made a 40-page PDF) |
| 21 files | Refused: "You can merge up to 20 files at once." |
| One file is not a PDF | The whole merge is refused. Nothing is merged without it. |
| A file that needs a password to open | Refused as "not a valid PDF or is corrupted" |
| A file with only an owner password (printing or editing restrictions) | Failed with a general error in our test |
Each file can be up to 20 MB and 200 pages. The tool does not remove passwords or restrictions; remove them in the program that created the file, then merge.
What this does not do
The tool joins pages. It does not recompress anything, so the merged file is about as big as the files together; use Compress PDF afterwards if it is too large to send. We have not verified how document-wide features such as bookmarks or form fields are carried over, so check the result if you depend on them. To put images into the combined file, use Image to PDF first. The guide PDF page ranges explained covers the next step if you then need only part of the result.
Compatibility
Supported Formats
Accepts PDF files only, identified by their contents: two to twenty per merge, each up to 20 MB and 200 pages. Password-protected files are not supported. The result is one PDF.
Guide
How to Use Merge PDF
- Choose two to twenty PDF files, each up to 20 MB.
- Use the up and down controls to put them in the order you want.
- Click "Merge PDFs" and download the combined PDF.
- Scroll through it once to check the order and the page sizes.
Highlights
Features
- Your order Files are joined exactly in the order listed; nothing is sorted for you.
- Page sizes unchanged A4, Letter and A3 pages merged in our test kept their own sizes.
- All or nothing If any file cannot be read, the whole merge is refused instead of leaving it out.
Applications
Use Cases
- Joining a cover letter, a form and supporting documents into one submission
- Combining separately scanned pages that each came out as their own PDF
- Putting several invoices or receipts into one file
- Adding a one-page PDF made from a photo to a longer document
Good to Know
Limitations
At most 20 files per merge. Pages are joined as they are: no resizing, no page-by-page reordering and no recompression. Files that need a password, and files with restrictions, may fail. We have not verified how bookmarks or form fields are carried over. The merged file is named merged-document.pdf.
Files are processed on our servers and are not shared with third parties. Files are deleted as soon as processing or download finishes. Any leftover temporary file is removed automatically by our cleanup process within the configured retention period (60 minutes). See our Privacy Policy for full details.
Support
Frequently Asked Questions
How many PDFs can I merge at once?
Two to twenty, each up to 20 MB. Twenty files merged in our test; twenty-one were refused with a message saying the limit is 20.
In what order are the pages joined?
In the order the files are listed. Use the up and down controls to change it before you merge. Pages inside each file keep their own order.
Why was my merge refused when only one file looked wrong?
Every file is checked first. If one cannot be read, the merge stops, so you never get a result with a file silently missing.
Can I merge a password-protected PDF?
No. A file that needs a password to open is rejected, and a file with only editing or printing restrictions failed with a general error in our test. Remove the protection in the program that made the file, then merge.
Will pages of different sizes be resized to match?
No. Each page keeps its own size, so an A4 file merged with a Letter file gives a document with both. The PDF Page Size Analyzer shows every page's size.
Keep Going
Related Tools
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