Merge PDF
Combine several PDFs into one file in the order you choose. Files never leave your device.
No upload · Processed in your browserPDF200 MB total (recommended)Up to 50 filesAs of 2026.09.30
Bookmarks and form fields aren't carried over. Page rotation and annotations are kept.
How to use
- 1Drag and drop two or more PDFs or pick them with [Choose files]. Each file shows its page count and a thumbnail of its first page
- 2Drag rows or use the up and down buttons to set the order, then press [Start]
- 3Save the merged PDF (merged.pdf) with [Download]
The big number on the result card is the page count of the merged PDF. The result is named merged.pdf; with “Name after the first file” turned on, -merged is added after the first file’s name, as in contract.pdf → contract-merged.pdf.
You can add up to 50 files at a time. We recommend a combined total of up to 200 MB on desktop and 50 MB on mobile. Going over the recommendation shows a warning, but you can still continue. Files that would bring the total over 500 MB can’t be added.
- Example 1 · Merging two PDFs
a-3p.pdf (3 pages, 2 KB) + b-2p.pdf (2 pages, 1 KB)
Measured in Chrome on desktop · test PDF with one large label per page
→ merged.pdf 5 pages · 1 KB · page order A-1, A-2, A-3, B-1, B-2
- Example 2 · Changing the order
The same two files · b-2p.pdf moved to the top with the up button
Measured in Chrome on desktop · test PDF with one large label per page
→ merged.pdf 5 pages · page order B-1, B-2, A-1, A-2, A-3
- Example 3 · A password-protected PDF in the mix
a-3p.pdf + encrypted.pdf (password-protected PDF)
Measured in Chrome on desktop · test PDF
→ Only encrypted.pdf is left out, with “Password-protected PDFs can't be processed” · with just one PDF left, [Start] is disabled
Example figures vary by file and device.
Options explained
- File order
- Files are merged from the top of the list down. Drag rows to move them, or use the up and down buttons on each row. The up and down buttons also work with the keyboard. Each row shows its page count and a thumbnail of the first page, so you can check the order as you arrange it.
- Name after the first file
- By default the result is named merged.pdf. Turn on “Name after the first file” and it's named after the file at the top of the list, as in contract.pdf → contract-merged.pdf. Useful when you want to tell apart the results of several merges.
- What gets merged
- This isn't a setting you can turn on or off; it always works the same way. Every page of every file is copied as is. Page rotation and annotations are kept, but bookmarks and form fields are not carried over. The result's document properties (title, author and so on) are left empty. If a document needs its bookmarks or form fields, keep the original as well.
Frequently asked questions
Are my PDFs sent to a server?
No. Merging happens inside this browser and your files are never sent off your device. To check it yourself, follow the steps on the How it works page.
Can I merge password-protected PDFs?
No. When you add a password-protected PDF, that file alone shows “Password-protected PDFs can't be processed” and is left out of the merge. Remove the password and add it again. Even a PDF that doesn't ask for a password when you open it may show the same message if it has a password restricting printing or editing. If two or more other PDFs remain, you can merge them as usual; if only one is left, [Start] can't be pressed.
It says “The file is damaged or was not fully saved”.
That means the file couldn't be read as a PDF. It can happen with a file whose download was cut off partway, for example. Save the original file again, then add it. Only that file is left out, and the other PDFs can still be merged.
Can I merge only certain pages?
Merging includes every page of each file. If you need only some pages, first pull them out with “Extract into one file” in Split PDF, then merge.
Does merging reduce quality?
No. Pages aren't turned into images; the text and images inside the PDFs are copied as they are, so quality doesn't change. The merged file's size isn't necessarily the sum of the originals: merging the two test files (2 KB and 1 KB) gave 1 KB.
Related tools
How it works · Engine · Notes
- Processed in: this browser (your device)
- Engine: pdf-lib (MIT) · PDF.js (page thumbnails) (Apache-2.0)
- Merging runs inside this browser with pdf-lib, and files are not sent to a server.
- Page rotation and annotations are kept; bookmarks and form fields are not carried over.
- The result's document properties (title, author and so on) are left empty.
- Page thumbnails are drawn with PDF.js for display only and don't affect the result file.
- As of 2026.09.30
- Changelog: 2026.09.30 First release