PDF Merge — Combine PDFs
Combine multiple PDF files into a single PDF. Nothing is uploaded to any server — all processing is 100% in your browser.
Click to add PDF files or drag & drop
Select multiple PDFs — all will be merged in order
How to Merge PDF Files Locally & Securely
Combining multiple PDF documents into a single organized file is essential when assembling contracts, job applications, or monthly invoices. Our Free PDF Merger runs entirely in your browser using WebAssembly and PDF-Lib, meaning your confidential files are never uploaded to any remote server or stored in the cloud.
Browser Processing Tips & Limitations
- Original Quality Preserved: Vectors, selectable text fonts, form elements, and high-resolution graphics remain intact without re-compression or DPI loss.
- Encrypted PDFs: If a document has owner or user password protection, remove the password before merging, as browser engines cannot decrypt proprietary owner locks.
- Memory Limits: Because processing occurs in your device's RAM, combining up to 50–100 regular documents (under 200MB total) executes smoothly on both mobile and desktop.
Frequently Asked Questions
Does merging PDFs reduce image or text quality?
No. Our merger copies the raw document streams directly page-by-page. Unlike converters that flatten pages into images, all vector fonts, lines, and embedded images maintain 100% of their original sharpness.
Why is my combined PDF file size so large?
When joining several PDFs created by different applications, each file may carry its own embedded font subsets and metadata dictionaries. If the output is too large for email, you can compress individual images before combining them.
Can I change the order of pages before merging?
Yes. Files are merged in the exact order they appear in the file list above. Use the remove button (trash icon) to adjust files and add them in your desired sequence before clicking 'Merge PDFs'.