Merge PDF

Key takeaways

• Runs in your browser (dynamic import / local processing)
• File bodies are not uploaded to our servers for these tools
• Size and page limits protect tab performance
• Quality claims stay honest for lossy converters

What does merge PDF mean?

Merging concatenates pages from several PDFs into one output file, preserving page order.

Use it when contracts, scans, or exports need a single attachment. This tool copies pages with pdf-lib locally rather than sending files to a hosted merger.

Features

• Multi-file merge

  Combine many PDFs in one pass.

• Local processing

  Files stay on-device during the merge.

• Standard PDF output

  Download a single merged .pdf.

• Clear limits

  Size and page caps keep the tab responsive.

How it works

1. 1

   Add your file(s)

   Drop PDFs or images into the workspace. Processing stays on your device.

2. 2

   Choose options

   Set page ranges, rotation, or format when the tool needs them.

3. 3

   Run & download

   Execute locally, then download the result Blob — nothing is uploaded.

Example walkthroughs

• Two contracts

  Produces one PDF with A’s pages followed by B’s pages.

  agreement-a.pdf + agreement-b.pdf

• Scan packet

  Builds a single packet for email or upload portals.

  cover.pdf + body.pdf + appendix.pdf

Use cases

• Email attachments

  Combine related PDFs before sending one file.

• Application packets

  Assemble forms and supporting docs in order.

Code snippets

• Process locally

  js

  Matches the privacy model for file utilities on this site.

  // Files stay in your tab — processors run via dynamic import / worker path
  // No multipart upload of PDF bodies for these tools.

Common errors

• File too large

  Cause: PDF/image exceeds the per-file byte limit.

  Fix: Split the document or compress scans before uploading to the workspace.

• Encrypted / unreadable PDF

  Cause: The file is password-protected or severely corrupted.

  Fix: Remove the password locally first, or try Repair PDF for mild structural issues.

About Merge PDF

Merge PDF combines two or more PDF files into a single document so you can send one attachment instead of a zip of scans, contracts, or exports. Page order follows the order you add files in the workspace.

Unlike hosted mergers, processing uses a local PDF library in your tab. That keeps sensitive packets, HR forms, and internal decks off third-party upload pipelines while still producing a standard PDF download.

Limits on file size and total pages protect the browser from freezing on huge books. If a merge fails, check for encryption or corruption and try Repair PDF for mild structural issues.

Best practice: put files in the final reading order before merging, and compress afterward only if you need a smaller email attachment. Prefer Split PDF when you need a subset of pages from one file rather than concatenating many. Keep originals until you confirm the merged packet opens in your target viewer.

Frequently asked questions

Explore more

• All developer tools

  Browse formatters, converters, PDF utilities, and more.

• PDF tools

  Merge, split, rotate, compress, and convert PDFs in your browser.

• Privacy

  How client-side and worker file tools handle your data.