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Merge PDF Files Online

Combine two or more PDF documents into a single file with our free PDF merger. Whether you are consolidating reports, joining scanned pages, or assembling a portfolio, the merge runs entirely inside your browser — your documents are never uploaded to any server. Files are combined in exactly the order you add them, preserving all pages, bookmarks, and quality.

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Choose files or drag & drop here

.pdf · multiple files allowed

Processed locally in your browser — your files never leave your device.

How to merge PDF

  1. Click "Choose files" or drag and drop two or more PDF files into the upload area.
  2. Arrange the files in the order you want them to appear in the final document.
  3. Click "Merge PDF" and download your combined document instantly.

Verified behavior and practical limits

Last tested:

How it processes your file

The selected PDFs are read and combined in your browser. Original files are not uploaded and are not modified.

Verified behavior

  • Every source page is copied into one PDF in file-selection order.
  • Mixed page sizes and orientations are preserved.
  • Pages are copied without rasterizing their text or vector content.

Important limits

  • At least two readable, unlocked PDFs are required.
  • Available device memory limits how many very large files can be combined at once.

Reproducible example workflow

Input
A two-page cover.pdf followed by a three-page report.pdf.
Action
Select the cover first, the report second, then run Merge PDF.
Expected output
merged.pdf with five pages: both cover pages followed by all three report pages.

Frequently asked questions

What's the best software for merging PDF files?

The best choice should preserve page quality, support multiple files, and protect private documents. 1PDF copies pages without recompression and performs the merge locally in your browser, with no upload or signup.

Is it safe to merge PDFs here?

Yes. Unlike most online PDF tools, all processing happens locally in your browser using WebAssembly. Your files are never sent to a server, so confidential documents stay private.

How many PDF files can I merge at once?

There is no hard limit on the number of files. Practical limits depend on your device memory — merging dozens of typical documents works smoothly on any modern computer or phone.

Will merging reduce the quality of my PDFs?

No. Pages are copied losslessly into the merged document. Text stays selectable, images keep their original resolution, and no re-compression is applied.

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