Split a PDF by file size

Cut an oversized PDF into parts that each stay under a limit you set, such as the 10 MB an email server will accept.

Drop your files here

.pdf · up to 300 MB

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How to Split by size

1
Add your PDF
Drop the file in or pick it from your device. Nothing is sent anywhere, so even a heavy scan is ready in a moment.
2
Set the maximum size per part
Type a number in megabytes or kilobytes, or take a ready limit such as 10 MB for email. Strict mode keeps every part under the number.
3
Download the ZIP with all parts
Press the button and save the archive. Inside are the parts in reading order, numbered so they stay easy to sort.

Why the parts have different page counts

Weight in a PDF is not spread evenly. A page of plain text costs a couple of kilobytes; a full-page photograph or a scanned sheet costs hundreds. Fonts, logos and other shared resources are stored once and counted once, so twenty pages are rarely twice the size of ten. Because of that, this tool never guesses. It adds pages to the current part, saves it for real, and measures the bytes that came out. When the next page would push the part past your limit, the part is closed and a new one starts. That is why a text chapter may fill one part with ninety pages while a photo section fills the next with four.

Strict limits, oversized pages and rebuilding the file

Strict mode is on by default because mail servers reject an attachment that is even slightly over. Turn it off and a part may overshoot by up to ten per cent, which usually means noticeably fewer files. A single page heavier than the whole limit cannot be split any further, so it is written out on its own and marked in the file name. Parts keep the original page order, and merging them back gives you the document you started with.

Where your file is processed

Splitting happens inside your browser tab, on your own processor. The PDF is never uploaded, never queued on a server, and the finished parts are packed into the archive on your own machine before the download starts. There is no account, no email step and no log of what you split. Close the tab and every copy is cleared from memory with it.

Frequently asked questions

Why do the parts have uneven page counts?

Because pages weigh different amounts. Text pages are tiny, scans and photographs are heavy, and shared fonts count once. Each part is filled until the next page would break your size limit, so page counts follow bytes, not a fixed number.

What happens if one page is heavier than the limit?

That page is written out as its own part and marked with an oversize suffix in its file name. Nothing can make a single page smaller without recompressing it, so compress that page to a target size in Compress PDF first if the limit is hard.

How is this different from compressing a PDF?

Compression shrinks one file by re-encoding images and fonts, which costs quality. Splitting keeps every page as it is and spreads the pages across several files. Use compression when you need one file, splitting when several are fine.

Can I put the parts back together?

Yes. The parts keep the original page order and are numbered in sequence, so merging them in that order rebuilds the document page for page. Nothing is re-encoded on the way out, so the merged file matches the original content.

Is the size limit respected exactly?

In strict mode yes: every part is saved and measured, and a part is closed before it can pass your number. With strict mode off, a part may run up to ten per cent over in exchange for fewer files.

How many parts can it produce?

Up to two hundred. Past that the result stops being useful and the tool asks for a larger limit instead, because two hundred attachments is no longer a solution to an attachment size problem.

Does my file go to a server?

No. The document is opened, cut and packed by your browser. It never leaves your device, there is nothing stored for us to see, and no account is involved at any point.