MRGMerge PDF

About this tool

How to use it

1. 01

   Add the PDFs you want joined

   Select several at once, or add them in batches. Files are read in the browser and never uploaded.

2. 02

   Drag to set the order

   The merge order is exactly the list order; filenames and the order you added them are irrelevant. Numbered filenames are not sorted automatically, so trust the list, not the names.

3. 03

   Check the page count and the seams

   Confirm the total before exporting, and look at the joins between documents. The usual failure is not a failed merge; it is a document in the wrong place or one that never got added.

4. 04

   Export the merged document

   You get a single PDF. If you need to separate it again later, Split PDF cuts by page range; provided you know how many pages each original contributed.

Supported range and limits

Page content

Lossless; nothing is re-rendered, pages are pixel-identical to the originals

Page size

Each document keeps its own size and orientation, so a merged file can be mixed-size

Bookmarks and forms

May not follow the pages; verify after merging

Encrypted files

The open password must be removed first with PDF Encrypt / Decrypt, or the pages cannot be read

Ordering

List order, drag to change; never sorted by filename

Size limit

Bounded by browser memory; very high page counts or lots of high-resolution images can fail

When you would use it

• Combining separately signed documents

  The body, the annexes and the signature page are often produced separately. Merging makes one file to archive and send; and because nothing is re-rendered, stamps and signature images lose no quality at all.

• Reassembling a scan

  Scanners frequently emit one file per batch. Merging in the right order restores a single complete document, which beats opening five files in a reader.

• Assembling a submission from mixed sources

  A report, chart exports and a converted Word explainer can become one submission file. Mismatched page sizes still merge fine; the pages simply change size as the reader moves through them.

What to know before you start

• Confirm the order before exporting. Nothing is sorted by filename; 01, 02, 03 in the names will not arrange themselves, and the sequence is purely what you see in the list. This is the most common way a merge goes wrong.
• A PDF with an open password cannot be merged directly, because its page content is encrypted. Remove the password first with PDF Encrypt / Decrypt; assuming you know it and are entitled to open the document; then merge.
• Bookmarks, some form fields and annotation relationships can be lost. If the original relied on form logic, fill the merged version in once to check it still behaves.
• Merging is one-way. Split PDF can cut by page range afterwards, but the original file boundaries are no longer recorded anywhere, so you need to know the page counts yourself. Keep the originals.

Related concepts

Page object

The internal structure representing one page of a PDF. Merging moves these objects rather than redrawing the page, which is why quality is unaffected.

Bookmarks / outline

A PDF's navigation tree, stored separately from page content. It references page positions, which is why it is the first thing to break when pages are reorganised.

Open password vs permissions password

An open password encrypts the content and is required to read the pages at all; a permissions password only declares restrictions on printing and copying. Merging is blocked by the former and unaffected by the latter.