How to Merge PDF Files Online (Free & Private)

Combining PDFs — contracts, scanned pages, reports — is one of the most common document tasks. Most online mergers upload your files to their servers. Here's how to do it privately instead.

Step by step

Open the Merge PDF tool, add the PDF files you want to combine, drag them into the order you want, and click merge. Your combined PDF downloads instantly.

Why it's private

Crystal Toolkit merges PDFs in your browser using the open-source pdf-lib engine. Your documents never leave your device, which matters for anything confidential.

Related PDF tasks

Need the opposite? Use Split PDF to extract pages. To shrink the result, try Compress PDF, and to fix orientation use Rotate PDF. See all PDF tools.

Tips for clean merges

Put the cover or summary page first, keep file names descriptive so ordering is easy, and compress afterwards if you plan to email the result.