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TabBench

Merge PDF

Combine multiple PDF documents into a single organized PDF file entirely client-side in your browser.

Runs in your browser. Nothing you add is uploaded.

What the Merge PDF does

Merging combines several PDFs into one document with pages in the order you choose. It is the fix for the very common situation where a form, an application, or a submission portal accepts exactly one file and you have six. This merger uses pdf-lib in your browser, so contracts, statements, and identity documents are assembled locally and never uploaded.

How to merge PDF files

  1. Add all the PDFs you want to combine — select several at once, or add them one at a time.
  2. Drag to reorder until the sequence is right. Pages appear in the final document in exactly this order.
  3. Remove any file you added by mistake.
  4. Merge and download the combined PDF.

The Merge PDF runs entirely in your browser — nothing you enter is uploaded, stored, or logged.

When to use it

Assembling an application pack

Visa, loan, and admissions portals frequently accept one attachment. Merging a passport scan, proof of address, and supporting letters produces the single file they require.

Combining chapters or sections

Reports written in parts by different people end up as separate exports. Merging produces the deliverable with continuous page flow.

Consolidating monthly statements

Twelve monthly PDFs become one annual document, which is far easier to archive and to send to an accountant.

Good to know

  • Unlock any password-protected PDF before merging — encrypted files cannot be read by the merger.
  • Page sizes are preserved per source document, so mixing A4 and Letter originals produces a document with varying page sizes. Normalise beforehand if it will be printed.
  • Merging does not compress. Combining several large PDFs produces a file roughly the sum of the inputs; compress afterwards if there is a size limit.
  • Check the page order in the preview before downloading rather than after.

Frequently asked questions

Is it safe to merge sensitive documents?

Yes, merging happens on your device using WebAssembly/JavaScript. No PDF data leaves your computer.

Are my PDFs uploaded to a server?

No. Every file is read into your browser and the merged document is built locally with pdf-lib, then written straight to your downloads. Nothing is transmitted — which is the reason to use a client-side merger for financial and identity documents.

How many PDFs can I merge at once?

There is no hard limit; the constraint is available memory, since all documents are held in the tab during the merge. Dozens of ordinary documents merge without difficulty. Merging many very large scanned files may make the tab unresponsive while it works.

Does merging reduce quality?

No. Pages are copied across as-is, with their text, vector graphics, and embedded images intact. Merging is lossless — it is compression, not merging, that trades quality for size.

Can I merge a password-protected PDF?

Not while it is encrypted. Remove the protection first with an unlock tool, then merge the unprotected file.

Will bookmarks and form fields survive the merge?

Page content transfers reliably. Document-level features — bookmarks, form fields, and internal links — may not survive, and form fields with identical names across source documents can conflict. Flatten forms before merging if the filled values matter.

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