PDF Merger Online
Join several PDFs into one document, reordering them by drag or with accessible up/down buttons, and check page counts and sizes before you download the combined file. It works through pdf-lib in your browser, so your documents stay private.
- 100% free
- Private & safe
- Runs in your browser
Your files are processed securely in your browser and are not uploaded to our servers.
Why use Merge PDF?
Merge PDF works on your documents locally, so you get the result in seconds with no watermarks, no sign-up and no files leaving your device.
- 100% private: files are processed in your browser and never uploaded.
- Completely free, with no account, no watermarks and no usage limits.
- PDF (.pdf)
- Add two or more PDF files.
- Works on any device — desktop, tablet and phone — and is fully keyboard accessible.
What it can do — and its limits
- Combines several PDF files into one and lets you set the page order.
- Runs entirely in your browser with pdf-lib — files aren't uploaded.
- No fixed page cap; very large merges are limited only by your device's memory.
How to use Merge PDF
- Add two or more PDF files.
- Reorder them by dragging, or use the up and down buttons for keyboard and screen-reader access.
- Review each file's page count and size, and remove any you added by mistake.
- Click Merge, then download the single combined PDF.
Examples
- Combining a cover letter and a résumé into one PDF to send.
- Merging scanned receipts into a single expense document.
Worked example
Input
resume.pdf (2 pages) + cover-letter.pdf (1 page)
Output
combined.pdf — 3 pages in the order you arranged.
Supported formats & limits
- PDF (.pdf)
Limitations
- Password-protected or encrypted PDFs must be unlocked before merging.
- Very large documents depend on your device's available memory.
- Performance scales with total page count and file size.
Common problems & fixes
A password-protected PDF won't merge.
Remove the password/permissions first, then add it to the merge.
Pages ended up in the wrong order.
Drag the files (or pages) into the order you want before exporting.
Sources & references
Last verified August 2026.
Frequently asked questions
Are my PDFs uploaded to a server?
No. Merging happens locally in your browser and the files are never uploaded.
Can I change the order of the files?
Yes, drag to reorder or use the accessible up/down buttons on each file.
Is there a limit to how many PDFs I can merge?
You can merge up to 20 files at once; very large documents depend on your device's available memory.