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Merge PDF files

Combine any number of PDFs into one. Drag to reorder. Nothing is uploaded.

Merge PDF

Never uploaded

Your file is processed in this tab and never sent anywhere.

How to merge pdf

  1. Add your PDFs. Drop several files at once, or pick them one at a time. They stay in this tab.
  2. Put them in order. Drag the rows to reorder. Remove anything you added by mistake.
  3. Merge and download. One combined PDF, assembled here and saved straight to your device.

About merge pdf

Merging is the most common thing anyone does to a PDF, and it is almost always for a boring reason: a scanned contract arrived as four separate files, an expense claim needs every receipt in one document, a mortgage broker asked for six months of statements as a single attachment. The job is trivial. What is not trivial is that every mainstream tool asks you to upload the documents first, which means a bank statement or a signed agreement takes a round trip through somebody else's infrastructure to accomplish something your own computer could do in half a second.

This tool assembles the merged file in the browser tab. pdf-lib parses each document, copies the page objects across into a new document, and hands you back the bytes. There is no upload endpoint in the page. You can prove that: open developer tools, switch to the Network tab, and run a merge. Nothing outbound fires. When you close the tab, the working copies are gone from memory and nothing persists.

Order matters more than people expect, so the file list is drag-to-reorder rather than fixed to the sequence you happened to select. Files added from a multi-select come in alphabetically, which is usually right for scans named page1, page2, page3, and usually wrong for anything named by date. Check the order before you merge. You can remove any file from the list without starting over.

A merged PDF keeps the page content of every source document, including embedded fonts and images, so text stays selectable and searchable if it was selectable to begin with. Bookmarks, form fields, and annotations are not carried across — those live in structures that do not survive a simple page copy, and pretending otherwise would produce files that look right and behave wrong. If your sources are scans and you want the merged result to be searchable, run it through OCR afterwards.

What survives a merge

ElementCarried acrossNote
Page contentYesText, vectors, and images are copied intact
Embedded fontsYesText stays selectable and searchable
Page size and rotationYesMixed sizes are preserved, not normalised
Bookmarks / outlineNoRebuilt structures would not match the new page order
Form fieldsNoFlatten the form before merging if you need the values
Annotations and commentsNoPrint or flatten to PDF first to keep them visible

Merge PDF FAQ

How many PDFs can I merge at once?

There is no fixed limit in the tool. The practical ceiling is your device's memory, since every document is held in the tab while it works. A few hundred megabytes of combined input is fine on a modern laptop; a low-memory phone will struggle sooner.

Does merging reduce quality?

No. Pages are copied as objects, not re-rendered, so nothing is recompressed. The merged file is roughly the sum of the inputs in size. If that is too large for email, run the result through Compress PDF afterwards.

Can I merge a password-protected PDF?

Not directly. Open it in Unlock PDF with the password first, save the unlocked copy, then merge that. A file that will not open cannot have its pages copied.

Why is my merged file in the wrong order?

Multi-selected files are added in the order the browser reports them, which is usually alphabetical rather than the order you clicked. Drag the rows into the sequence you want before merging.

Are my documents uploaded anywhere?

No. The merge runs in this browser tab using pdf-lib. There is no server endpoint to receive a file. Open the Network tab in developer tools and run a merge if you want to confirm it.

Can I merge images and PDFs together?

Convert the images to PDF first with Image to PDF, then merge the results here. Mixing formats in one step tends to produce surprising page sizes.

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