PDF Merger
Combine multiple PDF files into one document. Drag and drop to reorder pages.
Drop PDF files here
or
Supported formats: .pdf — multiple files supported
What Is PDF Merging?
PDF merging is an online tool that combines multiple PDF files into a single document. It's useful for consolidating scattered documents for distribution, integrating multi-page scanned documents, and streamlining PDF management.
sakutto.ai's PDF merger processes everything in your browser — your PDF data is never sent to any server. You can safely merge confidential files like invoices and contracts without privacy concerns.
Reorder files with drag-and-drop and preview content before merging. Ideal for consolidating meeting materials, compiling reports, or assembling application documents. Free, no sign-up required.
How to Merge PDFs
- Drag & drop the PDF files you want to merge, or use the file picker to add them
- Rearrange the file order by dragging or using the arrow buttons
- Click "Start Merge" to combine
- Download the merged PDF
Features of sakutto's PDF Merger
- Runs entirely in your browser — PDF data is never sent to a server
- Drag & drop to intuitively reorder files
- No quality loss — merging preserves the original quality
- Responsive design that works on smartphones too
- Free to use, no sign-up required
Why PDF Merger on sakutto is safe
Many online tools upload your files to external servers for processing. This tool never sends your PDF files to any server — everything is processed entirely in your browser.
* Some AI-powered tools require server-side processing. Tools that send data to a server will always notify you beforehand.
| Comparison | Typical online tools | sakutto |
|---|---|---|
| Where data is sent | Uploaded to external servers | Nowhere — processed in your browser |
| Data leak risk | Risk during transfer and server storage | No risk — no network transfer occurs |
| External traffic | File data travels over the internet | No file data appears in network logs |
| Offline use | Not possible (server required) | Works offline after initial load |
How browser-based processing works
- WebAssembly (WASM): Processes PDF files in your browser at near-native speed. No server communication occurs.
- Web Workers: Runs on a background thread separate from the main thread, so your browser stays responsive during processing.
- After processing, your browser automatically frees the data from memory. No PDF files remains outside your device.
For IT security teams: How to verify
You can verify that sakutto never sends your PDF files externally by checking the Network tab in your browser's DevTools while using the tool. You'll see that no requests involving your PDF files are made. This can also serve as documentation for your IT security team.
Frequently Asked Questions
Are my files uploaded to a server?
No. All processing is done entirely in your browser — your PDF files are never sent to any external server. You can safely use this tool even with confidential documents.
Is there a limit on the number of files I can merge?
The free version supports up to 5 files per merge. It depends on your device's memory, but typical files can be merged without issues.
Does merging affect the PDF quality?
No. Merging simply copies pages as-is, so text, images, fonts, and other content remain identical to the originals.
Can I change the merge order?
Yes. Drag & drop the files or use the up/down arrow buttons to arrange them in any order.
Can I merge password-protected PDFs?
Password-protected PDFs are not currently supported. Please remove the password before using the merger.
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