Merge PDF — Combine Files in Your Browser
Merge PDF files in your browser and download one combined document—nothing is uploaded to a server. Steps: add two or more PDFs, reorder the list, merge, then download. Example: two one-page samples become a two-page PDF. Encrypted or damaged files fail with a clear error. Differs from Images to PDF, which starts from photos.
How it works
Add two or more PDFs, reorder with Up/Down if needed, click Merge, then Download. Page order follows the list. Everything runs locally after the PDF library loads.
Rules you should expect
How list order, copyPages, privacy, and failure cases work when you merge PDFs locally.
- Order: pages are copied in list order (top file first). Reorder before Merge.
- Engine: pdf-lib loads each PDF and copyPages into a new document—no server round-trip for your files.
- Privacy: bytes stay in the browser tab. The library script may load from a CDN.
- Limits: need ≥2 files; encrypted or corrupt PDFs fail with a readable error; very large sets may be slow in memory.
Example
Sample loads two one-page PDFs labeled A and B, merges in list order, and enables Download for a two-page merged.pdf.
Good fits
- Office: combine signed pages and attachments into one packet.
- Students: stitch homework chapters before submission.
- Ops: pack brand assets and specs into a single PDF handoff.
Frequently asked questions
Are my PDFs uploaded?
No. pdf-lib runs in your tab (the library may load from a CDN). Your PDFs are not uploaded to our servers.
How is this different from Images to PDF?
Images to PDF builds a PDF from photos. This tool joins existing PDF files into one document.
Can I change the merge order?
Yes—use Up/Down on each row. Merge uses the list order from top to bottom as the page order.
What about encrypted PDFs?
Password-protected PDFs usually fail to open here. Remove the password with an unlock tool you trust, then merge.
Will the result open in Acrobat or Preview?
Most desktop and mobile PDF readers open the merged file.
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Questions or feedback
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