Skip to content
1123.net
EN
1123.net

Language

Search tools

Filter the tool directory. Everything runs in your browser.

Type to filter tools. Press Enter to open the first result.

Merge PDF Files

This PDF merger joins several files into one document. Add the PDFs, arrange them in the order you need, and merge; the file is assembled locally and never uploaded.

Your data is processed locally in your browser and is not uploaded to our server.

or drop PDFs here

PDF · max 50 MB each

PDF files

No PDF files added yet.

    The list order becomes the page order.

    How to use this tool

    1. 1 Add two or more PDF files with the button or by dropping them.
    2. 2 Move files up or down until the order is correct.
    3. 3 Press “Merge PDFs” and wait for the page count and file size.
    4. 4 Download the combined document.

    Formula and calculation logic

    Page order

    Output pages = file 1 pages, then file 2 pages, …

    The merged document contains every page of every listed file, in the order the files appear in the list. Pages inside each file keep their original order.

    No re-encoding

    copyPages(source, indices)

    Pages are copied into a new PDF document rather than rasterised, so text remains selectable and images keep their original quality.

    Worked example

    Report and appendix

    A main report and a separate appendix must become one file.

    1. Add report.pdf, then appendix.pdf
    2. Confirm the order
    3. Merge and download

    The appendix pages follow the report pages. The page count is the sum of both documents.

    Reordering before merging

    A signed contract should come before its exhibits.

    1. Add all files
    2. Move the contract to the top
    3. Merge

    The list order controls the output order; no need to rename the files.

    Edge cases and accuracy

    Encrypted PDFs

    Password-protected files must be unlocked first. The merger reports an encrypted file instead of producing a broken document.

    Different page sizes

    Pages keep their original dimensions. A merge can therefore contain mixed A4, Letter or landscape pages without scaling.

    Large collections

    Merging happens in memory. Many large files can approach browser memory limits; merge in smaller groups if the tab becomes slow.

    Frequently asked questions

    Are my PDFs uploaded? +

    No. The files are read and merged in your browser; nothing is sent to a server.

    Can I choose the page order? +

    You control the file order with the up and down buttons. Pages inside each file stay in their original order.

    Does merging reduce quality? +

    No rasterisation takes place. Pages are copied into the new document, so text and images keep their quality.

    Can I merge password-protected PDFs? +

    Not directly. Remove the password with the original application first, then merge the unlocked files.

    Is there a file limit? +

    Each PDF can be up to 50 MB. The practical total depends on available browser memory.