Drop PDF files here
or click to browse from your device
Merge PDF Files
Combine multiple PDFs into a single document. Drag to reorder, pick page ranges, and download — all processed privately in your browser.
Everything you need to merge PDFs
Powerful features that give you full control over how your PDFs are combined
Drag & Drop Upload
Drop multiple PDFs at once or click to browse. Files are validated instantly.
Visual Reordering
Drag file cards to rearrange merge order. Live preview updates as you reorder.
Move Up / Down
Precise arrow controls to nudge any file into the exact position you need.
Remove Individual Files
Remove any file from the queue without clearing the entire list.
File Details Display
See filename, page count, and file size for every uploaded PDF at a glance.
Total Page Counter
Live total page count across all files so you know your merged document size.
Total Size Indicator
Real-time total file size calculation helps you stay within email limits.
Custom Output Filename
Name your merged PDF whatever you want before downloading.
Add More Files Anytime
Keep adding PDFs to the queue even after your initial upload.
Clear All Button
One click to reset the entire workspace and start fresh.
Page Range Per File
Specify which pages from each PDF to include — skip covers, appendices, etc.
Bookmark Preservation
Toggle to keep or strip bookmarks from source PDFs in the merged output.
Merge Progress Bar
Visual progress indicator shows exactly how far along the merge process is.
100% Client-Side
Files never leave your browser. Zero uploads, zero servers, total privacy.
Sort by Name / Size
Quick-sort the file queue alphabetically or by file size for fast organization.
PDF Validation
Only valid PDF files are accepted. Corrupt files are flagged immediately.
How to merge PDF files
Three simple steps — no software, no signup, no upload
Add your PDFs
Drag and drop multiple PDF files onto the drop zone, or click to browse from your device.
Arrange the order
Drag file cards to reorder, use arrows for precise control, and set page ranges per file.
Merge & download
Click Merge PDFs, wait for the progress bar to finish, and download your combined document.
Frequently asked questions
No. Merge PDF runs entirely in your browser using pdf-lib. Your files never leave your device — there is no server upload, no cloud processing, and no temporary storage.
The only limit is your device's available memory. Most modern browsers can handle dozens of PDFs and hundreds of megabytes without issue. For extremely large batches, close other tabs to free RAM.
No. The merge process copies page objects directly from source PDFs without re-encoding images or re-rendering text. Fonts, images, and vector graphics are preserved at original quality.
Yes. Each page retains its original dimensions and orientation. You can mix A4, Letter, landscape, and portrait pages in a single merged document.
By default, bookmarks from each source PDF are preserved in the merged output. Form fields are kept intact. You can toggle bookmark preservation off if you prefer a clean output.
Yes. Use the page range field on each file card to specify which pages to include (e.g., 1-5, 8, 10-12). Pages outside the range are excluded from the merge.
Why merge PDFs with PDFly?
Real advantages over traditional PDF mergers
Complete Privacy
Your PDFs never leave your device. No servers, no uploads, no data collection — perfect for confidential documents.
Lightning Fast
No upload or download wait times. Processing happens instantly in your browser using WebAssembly.
Always Free
No subscription, no trial, no hidden fees. Merge as many PDFs as you want, whenever you want, completely free.
Your files stay on your device
Unlike online mergers that upload your PDFs to remote servers, PDFly processes everything locally
PDFly's Merge PDF tool runs entirely in your browser using client-side JavaScript and WebAssembly. Your sensitive contracts, financial statements, and legal documents are never transmitted over the internet. No servers to breach, no data to steal.
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