Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
PDF Merger
- Home
- Utility
- PDF Merger
Combine multiple PDF files into a single document directly in your browser. Your files never leave your device.
Drop PDF files here
or click to browse (max 10 files)
Maximum file size: 50MB each
What is a PDF Merger?
A PDF merger lets you combine multiple PDF files into a single document. You can upload up to 10 PDF files, drag to reorder them, and merge them into one cohesive PDF.
This tool runs entirely in your browser using the pdf-lib library. Your files never leave your device — they are not uploaded to any server.
How to Use This PDF Merger
- Upload PDF files — Drag and drop PDF files onto the drop zone, or click to browse and select multiple files (max 50MB each).
- Reorder the files — Drag the file handles to arrange them in the desired order for merging.
- Click Merge — Press the Merge PDFs button to combine all files into one document. Progress is shown in real time.
- Download the result — Click Download Merged PDF to save your combined document.
Frequently Asked Questions
Is this PDF merger safe?
Yes. All processing happens in your browser using JavaScript. Your PDF files are never uploaded to any server, stored, or logged.
How many files can I merge at once?
You can upload and merge up to 10 PDF files at once. Each file can be up to 50MB in size.
Can I reorder the files before merging?
Yes. You can drag the files up and down to reorder them before clicking the Merge button. The pages will appear in the merged PDF in the order shown.
What happens to the original files?
Nothing. The original files remain on your device. The merger creates a new PDF document by copying pages from your uploaded files.
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