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Merge 2 pdfs

Merging two PDFs is the most common merge there is, and the only thing that goes wrong is the order. The merge tool runs today, in your browser. It shows both files in the order they will be joined, lets you swap them, and checks every page and character of the result.

Merge PDF

Which file goes first

The tool joins files in the order they appear in its list, and the list follows the order you added them. That is rarely the order you want, because file pickers sort alphabetically and documents do not. A cover letter named "letter.pdf" ends up after a CV named "cv.pdf".

Move them before you merge. The order shown in the list is the order in the output, with no hidden rules and no sorting applied behind your back. Check it once and the rest is automatic: 2 files in, 1 file out, in the order you set.

What the check actually verifies

After the merge, the output is re-opened and read back. Page count is compared against the sum of the two sources, and the text of each page is compared against where it came from. If anything is missing, the merge fails rather than handing you a file that looks right.

That matters more than it sounds. A merge that silently drops an annotation layer or a form field produces a document that opens cleanly and is missing something you needed. Reading it back is the only way to know.

When two files is not the right shape

If you have five or six, use the multiple file page rather than merging in pairs. Doing it in pairs means four passes, four chances to get the order wrong, and no benefit.

If what you actually want is to interleave pages, or to put one document inside another rather than after it, merge first and then reorder with the organize pages tool. The two file merge guide walks through both cases.

Questions people ask

How do I control which PDF comes first when merging two files?
The output follows the order shown in the tool's list, and that list follows the order you added the files. Move them in the list before you merge. Nothing sorts them behind your back.
Does merging two PDFs lose the text?
No, and the tool proves it. The merged file is re-opened and its pages and characters are compared against both sources. If anything is missing the merge fails instead of shipping a damaged file.
Can I merge two PDFs if one of them has a password?
Not while it is locked. Remove the password first with the protect and unlock tool, using the password you already know, then merge the unlocked file. Nothing here breaks encryption.
Is there a size limit when merging two PDFs?
Not a fixed one. Both files have to fit in the browser tab at once along with the result, so very large documents can exhaust the tab's memory. Two normal documents are nowhere near that limit.

Do it now

The tool runs in this browser. Your file never leaves the machine, and the result is checked before you download it.

Merge PDF

Where to go next