MultiKit

Merge PDF: Combine PDF Files into One, No Upload

  • Free
  • No sign-up
  • Runs in your browser
  • Version 1.0.2
  • Last updated 2026-11-09
Report a problem

Join PDFs in the order you want. You can see every page, move or remove pages, and save one file. Nothing leaves your device.

    Everything you enter is processed in your browser and is never sent to a server.

    Browsers:Chrome119+Edge119+Firefox121+Safari17.4+Opera105+Samsung Internet25.0+Browsers

    How to use

    1. Drop your PDF files onto the box, or choose them. Every page appears as a small picture, in the order the files were added.
    2. Move a page with the arrows, turn it, or remove it with the cross. Reverse order flips the whole list.
    3. Press Save PDF to download one PDF that holds all the pages in the order you see.

    Examples

    Contract.pdf with 3 pages and Annex.pdf with 1 page, added in that order
    → One PDF with 4 pages: Contract 1, 2 and 3, then Annex 1
    The merged file follows the list you see: files in the order added, and the pages of each file in their own order.
    An A4 file with 2 pages and a US Letter file with 1 page
    → One PDF with 3 pages: two A4 pages (595 × 842 points) and one Letter page (612 × 792 points)
    Pages are not scaled to a common size, so one file can hold pages of different sizes.
    A 3-page file, Keep only pages: 1, 1-3
    → A PDF with 4 pages: 1, 1, 2, 3
    A page number may be written twice, which copies that page, for example to repeat a cover sheet.
    Three PDFs of 10 pages each, remove the last page of each
    → One PDF with 27 pages

    How it works

    Merging here means building a new PDF from a list of pages. Every entry in the list is one page of one of your files, and when you save, the open-source pdf-lib library (the maintained @cantoo fork) copies the entries into an empty document in the order shown. Nothing is added to the pages, and nothing is redrawn.

    Before you merge

    Check Why
    Open the files that need a password and remove it Protected files cannot be read here
    Look at the page sizes A4 and Letter pages stay as they are, so a mixed file prints unevenly
    Look for links and form fields in the originals They may not survive the copy
    Keep the originals The merged file is a new one, and the originals are not changed

    Why the result is a new document

    Because the merge starts from an empty file, the details that belong to a whole document, such as its title, are not taken from any of the originals. That is a consequence of building a new file page by page, and it is why the title is empty until you set one. A page’s own settings are kept: a page that was stored turned a quarter turn is still turned in the merged file.

    What a merge does not do

    It does not shrink the file, since the page contents are copied as they are. To make a large merged file smaller, use the compress PDF page afterward. It does not read the text of the pages either, so it cannot sort the pages for you. The order is whatever you set.

    Merging is tested by building PDFs with known text on each page, joining them, and reading the result back with PDF.js to check that the text of every page is in the expected order. The page sizes, the page turns, the repeat of a page number and the empty title are tested the same way.

    Sources

    Frequently asked questions

    In what order are the pages joined?
    In the order of the list on the screen: the files as you added them, and the pages of each file in their own order. Move a page with the arrows to put it elsewhere, or press Reverse order to flip the whole list.
    Are pages of different sizes resized to match?
    No. Each page keeps its own size and its own turn. An A4 file and a Letter file give a PDF with both sizes in it. If a printer or a form needs one size, make the files the same size before you merge.
    What happens to the title and other details of the original files?
    The merged file is a new document. The title of the original files is not carried over, and the file is marked as made by MultiKit. If a title matters, set it afterward in a PDF viewer or editor.
    Are links, bookmarks and form fields kept?
    They may not be. Pages are copied with their text and pictures, but links, bookmarks, form fields and other interactive parts of the originals may be lost, so check the result if you rely on them.
    Is there a limit?
    Up to 500 pages in total and 100 MB for each file.
    Can I merge a file that has a password?
    Not here. A password-protected PDF has to be unlocked first with the program that protects it, and then added.
    Are my files uploaded to a server?
    No. The files are read and joined in your browser, so a contract or an invoice stays on your device.
    Can I take out pages instead of joining files?
    Yes. Remove the pages you do not want before you save, or type the pages to keep. To cut one PDF into several files, use the split PDF page.
    Version history
    • 1.0.2 — Adds how the pages are ordered, what happens to page sizes and the title, a checklist before merging, what a merge does not do, and examples that show them.
    • 1.0.1 — Makes the search title and description state the supported task, key formats and privacy benefit more clearly.
    • 1.0.0 — First release.

    Last updated: