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PDF UnderFree Online PDF Merge Tool

Combine multiple PDFs into one file — reorder freely.
Everything runs in your browser — your files never leave your computer.

Click or drag multiple PDF files here

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Download Merged PDF

How to Merge PDF

1

Upload Multiple PDF Files

Click the upload area above or drag and drop multiple PDF files onto the page. You can select several files at once or add them in batches. Each file shows its name and size after uploading.

2

Rearrange the File Order

After uploading, you'll see a file list. Use the up and down arrows to adjust the merge order, or click the remove button to drop files you don't need. The file at the top will appear first in the merged PDF. Get the order right before merging so you don't have to redo it.

3

Merge and Download

Hit "Merge" and the tool will combine all PDF pages in your chosen order into a single new PDF. The process is fast — usually just a few seconds. Once done, click to download your merged file.

Why Use Online Merge

No need to install Adobe Acrobat or other paid software — just open the page and start merging. You can freely rearrange file order and remove files you don't need.

The merged PDF preserves each file's original page size and layout without altering the content. No file count limits, no watermarks.

Free, no sign-up, no uploads — all processing happens right in your browser. Close the tab and everything is gone.

Common Use Cases

Consolidate contracts and attachments — Contract body, appendices, and signature pages in separate files? Merge them into one PDF for easier sharing and archiving. Merging guide

Combine scanned pages — If your scanner produces one PDF per page, you end up with dozens of separate files. Merge them into one complete document.

Assemble reports — Different team members wrote their sections in separate PDFs? Combine them into the final report.

Bundle job application materials — Merge your resume, cover letter, portfolio, and certificates into a single PDF for one-click uploads. Job seeker PDF guide

Things to Note

  • Bookmarks are not preserved — Bookmarks (table of contents) from individual PDFs won't carry over to the merged file. You'll need another tool to recreate them if needed.
  • Page sizes may differ — If your source files have different page sizes (e.g., A4 and Letter), each page keeps its original size in the merged PDF. They won't be unified automatically.
  • Merged file may be large — Merging simply puts all pages together, so the result is roughly the sum of all input files. If it's too big, use the Compress tool to shrink it to a specific size.

You May Also Need

Compress PDF

Merged file too large? Set a target size and compress it.

Rotate PDF

Some pages facing the wrong way? Rotate them before merging.