Drag & drop PDF files here
or
PDF files only
Processed entirely in your browser — your documents never leave your device
Files to merge
How it works
Add your PDFs
Drop any number of PDFs — or click to browse. Nothing is uploaded. Use ↑↓ buttons to reorder, or ✕ to remove a file.
Merged in your browser
pdf-lib combines all pages in the order shown, running entirely in your browser tab. Metadata from source files is not included in the output.
Download merged PDF
One click downloads the combined file. No watermarks, no page limits, no sign-up.
Merge PDFs without a server
Most online PDF mergers upload your documents to a remote server, merge them there, then let you download the result. That means your files — including any sensitive content — pass through a third party's infrastructure.
ClientSide merges PDFs using pdf-lib running entirely in your browser tab. The document data never leaves your device. This is especially important for contracts, financial statements, legal documents, or any file you wouldn't want stored on an unknown server.
What the merged file contains
Why trust ClientSide
- pdf-lib runs entirely in your browser tab
- Documents are read into RAM — never written to disk
- No network requests made for your files
- Cloudflare serves HTML/JS only — never your PDFs
- Download writes directly from browser memory
Frequently asked questions
Is there a limit to how many PDFs I can merge?
No. You can merge any number of PDF files. The only practical limit is your browser's available RAM — very large batches may be slow, but there is no enforced page or file count limit.
Can I reorder the PDFs before merging?
Yes. Use the ↑ ↓ buttons next to each file to reorder them. The merged PDF will follow the order shown in the list when you click Merge & Download.
Will the merged PDF contain metadata from the source files?
No. The output contains only page content — author names, creation dates, and software info from the source files are not included in the merged result.
Does this work with password-protected PDFs?
No. Password-protected PDFs cannot be read without the password. Remove password protection first using your PDF application, then merge with ClientSide.
Are my documents uploaded to a server?
No. All merging is done by pdf-lib running entirely in your browser tab. Your documents are read into RAM and the merged result is written directly to your Downloads folder. Nothing is transmitted over the network.
Will text, images, and links be preserved in the merged PDF?
Yes. pdf-lib copies pages from source PDFs faithfully. Text, images, vector graphics, and hyperlinks are preserved in the merged output.