S
SoSimple.tools
PDF tool

Merge & Split PDF Locally

Combine several PDFs or extract specific pages in seconds, with the work done in your browser’s memory so your files never reach our servers

Free & unlimited • No sign-up Runs in your browser: what you enter stays on your device

Click to select multiple PDFs

PDF files only. No fixed size limit; very large files depend on your device's memory.

    Files join in the order of the list; files added later go to the end. Use ↑ and ↓ next to each file to change the order before you merge.

    Status

    Waiting for files…
    On your device: your files are processed in your browser and never uploaded.
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    How to use this tool

    1. To combine files, open the “Merge PDFs” tab and select two or more PDFs; remove any file with the ✕ and add more if needed.
    2. Press “Merge & Download”: the files are joined in the order shown in the list.
    3. To pull out pages, open “Split / Extract”, select one PDF and type the pages, for example 1-3, 5, 8-10.
    4. Press “Extract & Download” to save a new PDF with only those pages.

    Worked example

    Say you have a 2-page invoice and a 1-page receipt that must go to accounting as one file. Select both in the merge tab, check the order and download a single 3-page PDF. Later, from a 20-page contract, you only need the signature pages: type 1-3, 5, 8-10 and you get a 7-page file. Pages always come out in ascending order, duplicates are dropped and page numbers beyond the document are ignored. Bookmarks and some interactive form fields may not carry over, and very large files depend on your device's memory.

    Methodology

    This tool uses the open-source pdf-lib library (version 1.17.1, served from this site) to read and rebuild PDF files inside your browser. Merging and extracting copy the original pages, with the fonts and images they use, into a new file. Nothing is sent to a server.

    Everything stays on your device: When you choose a file, the browser keeps it in your device’s memory and works on it there; the file itself is never sent anywhere. That is why the limit is your device: a phone may struggle with a file of several hundred megabytes that a computer handles easily.
    Pages are copied, not redrawn: Pages are copied as they are, not re-rendered, so text stays selectable and images are not recompressed. Fonts and images used by a copied page travel with it. Bookmarks, document-level outlines and interactive form fields may not carry over, and the merged file is usually close to the sum of its sources in size.

    PDF page-range mix-ups, and what this tool does with them

    Most surprises come from assuming the tool works like a full PDF editor. Here is what it actually does in each case.

    • Expecting several files from one extraction. Typing 1-3, 5 gives one PDF with four pages, saved as extracted-sosimple.pdf. For separate files, run it once per range and rename each download.
    • Assuming a merge order you did not check. Files join in the order of the list; files added later go to the end. Use ↑ and ↓ next to each file to change the order before you merge.
    • Typing the printed page number. Ranges count the position in the file: the first page is 1, even when the page itself is printed as “iii” or starts a chapter at “1”. A 12-page file ignores 15.
    • Selecting files that are not plain PDFs. Only files your browser reports as PDF are added; a Word file or image is skipped without a message. A PDF with encryption is refused with a message naming the file, so unlock it first.
    • Typing pages in the order you want them. Output is always ascending, so 5, 1 returns page 1 then page 5. To reorder, extract each page separately and merge the results in your order.

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    Frequently asked questions

    Why should I use this instead of popular online PDF tools? ▼

    Many online PDF services work by uploading your file to a server, which you may not want for contracts, payslips or ID scans. Here the files are processed inside your browser tab and the result is created on your device, so nothing is uploaded. That does not make the result a certified or signed document; it is a plain copy of the pages you chose.

    Is there a maximum file size limit? ▼

    There is no fixed limit in the code. Because each file is loaded into your browser's memory, very large PDFs (hundreds of megabytes) may fail on older phones or low-memory computers, and merging several large files needs memory for all of them at once. If the browser stops responding, merge in smaller groups.

    Can I process password-protected PDFs? ▼

    No. The tool cannot open encrypted files. Remove the password in your PDF reader first, then add the file here.

    How does the page range work when I split a PDF? ▼

    Separate single pages with commas and write ranges with a dash: 1-3, 5, 8-10 on a 12-page file extracts pages 1, 2, 3, 5, 8, 9 and 10. Pages outside the document (for example 15 in a 12-page file) are ignored, a reversed range such as 10-8 is read as 8-10, and duplicates are removed. The output always keeps the original page order, so 5, 1 still produces page 1 followed by page 5. If no listed page exists in the file, you get an error instead of an empty PDF.