What PDF Merge helps you do

Combine two or more PDF files into a single document without uploading them to Haivix. The file list shows the final order, and simple move and remove controls let you correct the sequence before the merged PDF is created. It is built for handoffs where several documents need to arrive as one file with a predictable page order.

PDFs are loaded and combined in your browser with a client-side PDF library. No document is uploaded to Haivix, and no merged copy is stored on a server.

How it works

The browser loads each PDF with a JavaScript PDF library, creates a new empty document, and copies every source page into it in list order. Pages keep their original dimensions and orientation, so the output is a straightforward page-by-page concatenation rather than a layout operation. The new file is assembled in memory and downloaded directly; nothing is sent to a server.

How to use PDF Merge

Add two or more PDF files, then move them into the order the recipient should read.
Remove any incorrect file, then merge and download the combined PDF.
Open the result and check the page order, orientation and page count before sending.
Unlock encrypted sources first if the merge cannot read them.

When to use it

Package a cover letter, proposal and supporting documents for one upload.
Combine scanned chapters or receipts into a single archive.
Join exported sections of a report that was split for size.
Assemble a reading packet in a deliberate order.
Merge records before sending them to a system that accepts one file.
Build a single packet from several signatures or approval notes.
Put a cover page and terms around a document without a desktop editor.

When not to use it

Do not merge files that are still being edited or signed; work from final versions.
Do not expect bookmarks, tags or form fields to survive in a structured way.
Do not use it to compress a large set; run the result through PDF Compress afterwards.

Example

A consultant sends a cover page, a ten-page proposal, two case studies and a terms sheet. The five files are ordered in the list, merged, and opened to confirm that the cover is first and the terms are last. The recipient gets one attachment instead of five. If the proposal is revised the next week, the same source files are reassembled in the same order, so the package stays consistent.

What you can do with PDF Merge

Add multiple PDF files in one browser session.
Move documents up or down to control the final page sequence.
Remove an incorrect file before merging.
Keep the original page sizes and orientation of each source.
Create and download one combined PDF locally on your device.
Check the file list before committing the merge.

Example: assemble a client handoff

Add the cover page, proposal, supporting evidence, and terms. Arrange the files in the order the recipient should read them, then merge and open the downloaded PDF for a final page-by-page check.

For a long package, rename the source files with numeric prefixes before adding them. That gives you a reusable source order and makes future revisions easier to assemble.

If the package will be printed, check the paper sizes before merging. A mix of A4 and Letter pages is valid but produces an uneven printed stack, and some print workflows crop or scale the difference.

For a recurring package, keep the source files in a dedicated folder with stable names. Rebuilding the same packet later then takes a minute, and the recipient sees a consistent structure rather than a new ad hoc order.

What to know before you start

Encrypted or damaged source files may need to be unlocked or repaired before they can be merged.
Browser memory limits depend on the device, so very large scanned files can take longer or fail on low-memory phones.
Merging combines pages but does not automatically optimize image quality, bookmarks, form behavior, or file size.
Interactive forms and digital signatures are not merged into a new signing workflow.

Common mistakes

Adding files in download order and forgetting to reorder them before merging.
Merging encrypted documents that the library cannot read.
Assuming the result is smaller; merging usually adds a little overhead.
Leaving interactive form fields in a package that will be flattened later.
Skipping the final page-by-page check, which is when missing pages are found.
Merging a signed contract and expecting the signature to remain verifiable.
Combining Letter and A4 pages without checking how the printer will handle the difference.

Troubleshooting

If a file cannot be loaded, it may be encrypted, damaged or use a PDF feature the browser library does not support. Unlock or repair it in a PDF editor and try again.

If the merge fails on a phone, the combined document may exceed available memory. Merge fewer files per pass or use a desktop browser.

If the page order is wrong, the list order was wrong when the merge ran. Reorder the files and run it again; the merge does not sort pages on its own.

If a scanned document looks blurry, the source was already low resolution. Merging copies the pages and does not change their image quality.

If the merged file is larger than the sum of its parts, the new document carries its own structure and cross-reference data. Run it through the compressor if the size matters for upload.

If bookmarks or form fields behave differently, the merge is a page-level copy. Complex interactive features may need to be rebuilt or handled in a dedicated PDF editor.

PDF Merge