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Runs in your browser; files are never uploaded to Tool Lockers.

PDF Tools · Private, local processing

Merge PDFs

Combine PDF files into one document. Files are processed locally in your browser and are not uploaded.

PDF files up to 50 MB each and 100 MB combined. Files stay on this device; no upload or account is required.

Select at least two PDFs to merge automatically.

This tool runs in your browser. Very large or damaged PDFs may exceed available device memory; password-protected PDFs are not supported.

Free online tool

How to use Merge PDFs

Choose at least two PDF files to start the merge. The selected files appear in their current merge order; use the move controls to place each source document where it should appear in the combined file. Adding or removing a source PDF recalculates the preview automatically. Check the preview page by page before downloading, especially if the source documents use different page sizes or orientations. The merge runs locally in your browser, so the selected PDFs are not uploaded to Tool Lockers. Each file can be up to 50 MB and the combined selection is limited to 100 MB to avoid excessive device memory use. Password-protected or damaged PDFs may fail to load; unlock or repair them with software you trust, then try the resulting files. The download is a new PDF, and your originals remain unchanged. The preview is useful for confirming document sequence, but keep the source files until you confirm the merged PDF opens and contains all expected pages. If processing is slow, close other memory-intensive browser tabs and retry with a smaller selection.

How it works

  1. Select at least two PDF files from your device.
  2. Use the move controls to set the source-file order and wait for the merged preview.
  3. Review the combined document and download the new PDF.

Examples and common errors

Combine two reports

Input or situation

quarterly-report.pdf, appendix.pdf

Expected result or advice

One PDF with the report first and appendix second.

Change merge order

Input or situation

Cover.pdf, report.pdf, appendix.pdf

Expected result or advice

Move the files into the intended reading order before the merged preview is generated.

Common error

Input or situation

A password-protected or damaged PDF

Expected result or advice

Unlock or repair the source file with trusted software before merging it.

Frequently asked questions

Are my PDFs uploaded?

No. The browser reads the selected files and creates the merged PDF locally on your device.

Can I change the order before merging?

Yes. Use the up and down controls next to the files. The merged preview updates to reflect the new order.

Can I merge password-protected PDFs?

Encrypted PDFs are not supported. Unlock them using software you trust, then select the unlocked copies.

How many files can I merge?

Each PDF can be up to 50 MB and the combined selection is limited to 100 MB to help manage browser memory.

Will the original files be changed?

No. The tool creates a separate merged PDF; your source files remain unchanged.