PDF Merge

PDF Merge combines two or more PDF documents into one file in the order you choose. Each page is copied into a new PDF using pdf-lib in your browser, so page dimensions, text, and embedded images from the source files are preserved rather than re-rendered.

You can add up to 20 PDFs, each up to 20 MB, with a combined size limit of 40 MB. At least two valid PDFs are required before merging. The result downloads as merged.pdf.

1. Add PDFs by dragging them onto the drop zone or using the file picker. Only .pdf files within the size limits are accepted.
2. Arrange files in merge order: drag a row by its handle, use the Up and Down buttons, or focus a row and press Alt+Arrow (Windows/Linux) or Cmd+Arrow (macOS) to move it.
3. Remove individual files from the list or use Clear to start over.
4. Click Merge & download when at least two PDFs are ready. The browser builds the combined file and saves merged.pdf.

Merging is concatenation: pages from file one appear first, then file two, and so on. Bookmarks, form fields, and document-level metadata from sources are not merged into a unified structure; you get one continuous page sequence.

If two sources use different page sizes or orientations, each page keeps its own size. The tool does not normalize pages to a single format.

• Combine scanned receipts or invoices into one attachment for email or accounting.
• Append a cover sheet, terms page, or appendix to an existing report.
• Join chapter PDFs or handouts into a single reading file.
• Merge signed pages with an unsigned draft when both are already PDFs.

• Put the cover or table of contents at the top of the list before merging.
• Check total size before adding the last file; the 40 MB combined cap applies to all queued PDFs.
• If a file fails to load, confirm it is not password-protected, empty, or corrupted.
• After merging, use PDF Split if you need to extract or reorder pages in the combined file.

Merging runs entirely in your browser with pdf-lib. Your PDFs are read from disk into memory on your device and are not uploaded to ToolsArk servers or sent to a third-party conversion service.

Like any web page, your browser still loads the site over the network, and your operating system may cache downloads. ToolsArk does not receive the contents of your PDFs for this tool.

• Requires at least two PDFs; single-file upload cannot produce a merge.
• Maximum 20 files, 20 MB per file, 40 MB total across the queue.
• Password-protected or encrypted PDFs cannot be opened in the browser and will fail inspection.
• Does not edit page content, rotate pages, or compress file size; use PDF Compressor or Split for those workflows.
• Very large merges may be slow or hit browser memory limits on low-RAM devices.