PDF MERGER
Combine multiple PDFs into one file. Drag to reorder, then download — no upload required.
Drop your PDF files here
or click to select files
Up to 5 PDF files · Files never leave your device
How PDF Merging Works in Your Browser
AI Toolbox uses pdf-lib — a pure JavaScript library — to combine your PDF files entirely within your browser. Your files are never sent to a server.
How to Merge PDF Files
Upload your PDFs
Drop up to 5 PDF files into the upload area or click to select them from your device.
Reorder if needed
Drag the files into your desired order. The merged PDF will follow this sequence.
Merge and download
Click Merge PDFs, name your file, and download the combined PDF instantly.
Why Use AI Toolbox PDF Merger?
100% Private
Your PDF files never leave your device. All merging happens locally in your browser — no server, no cloud, no third-party access.
Drag-to-Reorder
Arrange your PDFs in any order before merging. Drag and drop to reorder, or use arrow buttons on touch devices.
Preserves Quality
Fonts, images, and embedded content from each PDF are faithfully preserved in the merged output.
Custom Filename
Name your merged file before downloading. No generic filenames — get the output exactly as you need it.
Frequently Asked Questions
Is this PDF merger really free?↓
Yes, completely free with no hidden costs, watermarks, or file limits. No account required.
Are my PDF files uploaded to a server?↓
No. All merging happens locally in your browser using pdf-lib. Your files never leave your device.
How many PDFs can I merge at once?↓
You can merge up to 5 PDF files in a single operation. Run the tool again to combine more.
Will the merged PDF preserve fonts and images?↓
Yes. pdf-lib copies each page along with its embedded fonts, images, and content. The output is a faithful combination of your source files.
Can I merge password-protected PDFs?↓
Password-protected PDFs cannot be merged. Remove the password protection in your PDF reader first, then retry.
What is the maximum file size?↓
There is no enforced file size limit. Very large PDFs (hundreds of MB) may take longer to process depending on your device's memory.
Can I reorder pages before merging?↓
You can reorder entire PDF files before merging by dragging them into your preferred sequence. Page-level reordering within a single PDF is not supported.
Does this work on mobile?↓
Yes. The tool works on mobile browsers. Tap and hold the drag handle to reorder files on touch screens.
Ready to merge your PDFs?
Drop your files above and get a merged PDF in seconds — no account, no upload.
Merge PDFs FreePrivacy & Security
AI Toolbox PDF Merger runs entirely in your browser. No PDF data is transmitted to any server. Processing uses the open-source pdf-lib library. Files are read from your local device and the merged result is downloaded directly to your device.