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Free Online PDF Merger - Combine Multiple PDFs

PDF Tools

What is Free Online PDF Merger - Combine Multiple PDFs?

PDF Merger is a utility for combining multiple PDF documents into a single file. Many online PDF tools require you to upload your sensitive documents to their servers for processing, which poses a significant privacy risk. Our merger performs all operations locally on your machine using WebAssembly. This ensures that your private contracts, medical records, or financial statements stay on your device throughout the entire process.

How it works

The tool uses the `pdf-lib` library compiled to JavaScript. When you upload files, it reads their binary data into browser memory, creates a new PDF document, and copies the pages from each source file into the new one. The final document is then saved and offered for download as a standard Blob.

Features & Benefits

  • Combines any number of PDF documents
  • Works entirely in your browser - absolute privacy
  • Fast processing even for large files
  • No file limits or account required

Frequently Asked Questions

Is there a limit on the number of files?

There is no hard-coded limit, but merging dozens of very large files may be constrained by your browser's available memory.

Are my files uploaded?

No. All merging happens 100% in your browser. Your files never touch our servers.

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