Different page sizes
A4, Letter and other page dimensions remain different inside the result. PDF viewers handle mixed sizes, but printed pages can scale differently. Use Resize PDF first if every sheet must be uniform.
Organize PDF tool
Merge PDF Online
Combine two or more PDF files in the order you choose, while retaining each page’s original dimensions and orientation.
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60 MB total on desktop · 25 MB on mobileStep 2 · Review and settings
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Three clear steps
How to merge PDF files
Add the complete source documents, arrange them in the required sequence and check the new file before using it.
- 1
Add two or more PDFs
Select the documents you want to combine. Keep an untouched copy of every source file.
- 2
Set the file order
Arrange the file cards from first to last. All pages from one file are added before the next file begins.
- 3
Merge, download and inspect
Open the downloaded PDF and check page order, orientation, bookmarks, links and forms before sharing it.
Before you combine files
How the merged PDF is built
The tool creates one new PDF by importing the pages of each source document in your selected file order.
File and page ordering
The order of the visible file cards controls the result. Pages within each individual PDF retain their original sequence. For page-by-page rearrangement, use Organize PDF.
Portrait and landscape pages
Mixed orientations are supported. Each page is added using its source width, height and corresponding portrait or landscape orientation.
Quality preservation
Pages are imported structurally rather than deliberately converted to screenshots. The merger does not intentionally downsample page images. Always inspect fine text and graphics in the actual download.
Current processing limits
Files, pages and upload size
These are application limits, not estimates. The host may reject a request earlier if its configured request limit is lower.
- Minimum files
- 2 PDFs
- Maximum files
- 100 PDFs
- Per-file size
- 20 MB
- Combined upload
- 100 MB
- Page count
- No separate fixed page maximum
A large number of complex, image-heavy pages may still exceed available memory or processing time even when the byte limits are met. Divide an unusually large job into smaller merges, then combine those results.
Document-level features
Bookmarks, metadata, passwords and forms
Merging visible pages is different from combining every document-level feature stored inside the source PDFs.
Bookmarks and metadata
The current merger does not explicitly combine outline bookmarks or source metadata into a unified structure. Check the title, author, subjects, bookmarks and attachments in the downloaded file if they matter to your workflow.
Password-protected PDFs
Encrypted files must be unlocked before they can be imported. If you know the password and are authorized, use Unlock PDF, then merge the unlocked copy. You can apply a new password afterward with Protect PDF.
Interactive forms
Do not assume that fillable fields, calculations, actions or signatures will remain interactive. Save completed field values where appropriate, preserve the original and verify the merged output in the PDF reader your recipient will use.
File handling
Privacy and file deletion
Your PDFs are uploaded only when you start the workflow. Uploaded and generated files are handled according to the published deletion lifecycle. Avoid sending highly sensitive material through any online service unless it meets your requirements.
Troubleshooting
When a merge does not look right
The files appear in the wrong order
Return to the original PDFs and arrange the visible file cards before processing. Filename order is not a reliable substitute for the displayed sequence.
One PDF cannot be processed
Open that file separately. If it requests a password, unlock it only with authorization. If it is damaged, try Repair PDF before merging.
Pages look uneven when printed
The source files probably contain different page sizes. Standardize them with Resize PDF or review the print dialog’s scaling setting.
The output is too large
Merging combines content; it is not a compression step. Download and verify the result, then use Compress PDF if a smaller file is required.
Merge PDF questions
Frequently asked questions
How many PDF files can I merge at once?
A request can contain up to 100 files. Each file can be up to 20 MB, and the combined upload can be up to 100 MB. Browser, memory and processing-time limits can affect unusually large jobs.
Is there a maximum number of PDF pages?
The merge operation does not impose a separate fixed page-count limit. The practical limit depends on the number, size and complexity of the files within the upload and processing limits.
Does merging reduce PDF quality?
The merger imports PDF pages into a new PDF rather than intentionally rendering them as images. This avoids deliberate image downsampling, but you should still inspect the downloaded result.
Can I merge a password-protected PDF?
Not while it remains encrypted. If you know the password and have permission, create an unlocked copy first and then merge that copy.
Are bookmarks and document metadata preserved?
Do not assume they will be. The merger creates a new PDF and does not explicitly combine source bookmarks or document-level metadata.
Will fillable PDF forms remain interactive?
Do not rely on interactive form fields surviving a merge. Their visible appearances may differ from their underlying form behavior, so flatten or verify forms before sharing the result.
Can I combine portrait and landscape pages?
Yes. Each imported page keeps its own page dimensions and orientation, so portrait and landscape pages can coexist in the merged PDF.
Continue your workflow
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