Merge PDF
Combine two PDFs, or fifty, into a single document in the order you choose. Each source file can get its own bookmark, blank scan backs can be dropped, and mixed A4 and Letter pages can be brought to one size.
Merge PDF
or drop PDF files here ·
Max 95 MB per file· Up to 50 files· Deleted after 30 minutes
Files are processed on our servers and deleted after 30 minutes.
Same as source keeps every page as it is. Pick a size to make all pages match, e.g. A4 for a mix of scans and Letter documents.
Fit scales each page to the new size. Keep size centres the original content without scaling.
How to use this tool
- 1
Upload the PDFs to combine
Add 2 to 50 PDF files, each up to 95 MB. Drag them in the list to set the order, or sort by name or date later.
- 2
Set the order and structure
Choose Merge in upload order, file name or date modified. Under Advanced settings, decide on bookmarks, blank pages, page size and form fields.
- 3
Merge and download
Press Merge and download one PDF that contains every page of every file in sequence.
How do I combine PDF files into one?
Upload the PDFs, put them in order by dragging or by choosing Merge in File name or Date modified, and press Merge. You get one PDF with every page in sequence and, by default, a bookmark at the start of each original file.
Why combine PDF files before sending them
Many upload forms accept exactly one file per field: one supporting document for a visa application, one attachment for an expense claim, one PDF for a grant proposal. If your evidence is spread over a cover letter, a bank statement and three receipts, merging is how you fit it into that one slot without printing and rescanning.
A single file is also easier for the person on the other side. They read one document from start to finish, print it once, and file it once. Bookmarks named after each original file act as a table of contents, which matters when a merged packet runs to dozens of pages.
Merging works on pages, not on content. Text stays selectable, images keep their resolution, and nothing is re-rendered. That means you can merge first and decide about compression later, and it means a merged file is only as tidy as its parts: rotate sideways scans with rotate PDF before you combine them. The guide how to merge PDF files covers merging on Windows, macOS and phones as well.
Two options shape how the merged file prints. Remove blank pages drops pages that carry no visible content, which is what a duplex scanner produces for every one-sided sheet. Start each file on an odd page does the opposite: it inserts a blank page where needed so that, printed double-sided, each original document begins on the front of a new sheet and can be separated by hand. Use one or the other depending on whether the merged PDF is meant to be read on screen or printed and handed out.
What happens when you merge PDF files online
Order
Files are lined up by upload order, natural file-name order or date modified.
Combine
Pages are copied in sequence; optional blank-page removal, duplex padding and page sizing run here.
One PDF
A single file with bookmarks per source, ready to download for 30 minutes.
Merging pages of different sizes
| Size | Pixels | cm | in | DPI | Fits |
|---|---|---|---|---|---|
| A4 | 2480 × 3508 | 21.0 × 29.7 | 8.27 × 11.69 | 300 | Standard outside the US and Canada |
| Letter | 2550 × 3300 | 21.6 × 27.9 | 8.5 × 11 | 300 | US and Canadian office paper |
| Legal | 2550 × 4200 | 21.6 × 35.6 | 8.5 × 14 | 300 | US contracts and court forms |
| A3 | 3508 × 4961 | 29.7 × 42.0 | 11.69 × 16.54 | 300 | Drawings and large tables |
| A5 | 1748 × 2480 | 14.8 × 21.0 | 5.83 × 8.27 | 300 | Booklets and half-sheet forms |
- Leave Page size on Same as source when every file already uses one paper size.
- Pick A4 or Letter when you mix scans, phone photos turned into PDFs and exported documents.
- Keep Content on Scale to fit so nothing is cut off; Keep size, centre adds white space around smaller pages instead.
- Turn on Remove blank pages for duplex scans with empty backs.
- Turn on Start each file on an odd page if the merged PDF will be printed double-sided and each document must start on a new sheet.
- Use Remove metadata to clear author, title and software fields carried over from the source files.
Merge PDF problems and fixes
A file is refused when you add it
It is encrypted. Remove the open password with unlock PDF, using the password you were given, then merge.
Pages appear in the wrong order
Name-based sorting reads the full file name. Rename files with leading numbers, or switch Merge in to Upload order and drag them into place.
Answers in one form appear in another
Both forms used the same field names. Merge again with Flatten forms turned on.
A signed document shows a broken signature
Merging creates a new file, so signature validation is lost. Send signed documents separately when the signature must be verifiable.
Merge PDF questions
How do I merge two PDFs into one?
Upload both files, check that they are listed in the right order, and press Merge. The second file's pages follow the last page of the first. With Bookmark per file on, the merged PDF also gets two bookmarks so readers can jump to the start of each part.
Can I merge images and PDFs together?
This tool combines PDF files. Turn photos or scans into PDF pages first with image to PDF, or JPG to PDF for camera photos, and then merge those pages with your other PDFs here.
Why are some pages a different size after merging?
Merging keeps each page at its original size by default, so a US Letter document and an A4 scan stay different. Set Page size to A4 or Letter with Content on Scale to fit to make every page match.
What happens to fillable forms when I merge them?
Form fields are carried over, but two forms that use the same field name end up sharing one value, so typing into one fills in the other. Turn on Flatten forms to turn the answers into plain page content before they can collide.
How do I merge PDFs and then convert the result to Word?
Merge first, download the combined PDF, then upload it to PDF to Word. Converting one merged file gives a single Word document with continuous page flow instead of several documents to paste together.
Does merging make the file larger than the originals combined?
It is usually about the sum of the parts or slightly less, because shared fonts and resources can be stored once. If the result is too large for an upload, run it through compress PDF afterwards.
In what order are files merged when sorted by name?
Natural order: file 2 comes before file 10, the way people count, not the way a plain alphabetical sort would place them. Name scans with leading numbers such as 01, 02, 03 if you want the order to be obvious to anyone else too.
How many PDFs can I merge for free at once?
Up to 50 files in one merge, each up to 95 MB. If you have more, merge them in groups of 50 and then merge the resulting files together; the bookmarks from the first round are kept when Bookmark per file stays on.