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Split PDF by File Size

Break a large PDF into parts that each fit under a size limit you choose. Every part is measured after saving, so it really fits.

Drop a PDF here or click to browseEvery part is measured after saving, so each one really fits

What is the Split PDF by File Size?

Email servers, upload forms and court filing portals all cap attachment size, and a scanned document can sail past 25 MB without looking especially long.

  • Splits on measured file size, not an estimate
  • Presets for Gmail's 25 MB cap and other common limits
  • Any custom limit in megabytes
  • Every part lists its exact page range and size
  • Warns clearly when a single page is larger than the limit
  • No upload — even a 200 MB file stays on your machine

How to use the Split PDF by File Size

  1. 1

    Drop the oversized PDF onto the upload area.

  2. 2

    Choose a maximum size per part from the list, or pick Custom size and type your own limit in megabytes.

  3. 3

    Click Split by File Size and wait while the pages are packed.

  4. 4

    Review the parts: each row shows its page range and its real file size.

  5. 5

    Download each part with its own button.

About the Split PDF by File Size

Email servers, upload forms and court filing portals all cap attachment size, and a scanned document can sail past 25 MB without looking especially long. Splitting it by page count is guesswork: pages vary enormously in size depending on whether they hold text or a full-page photograph.

This tool splits by the thing that actually matters. It adds pages to a new document one at a time, serialises the document after each addition, and starts a fresh part as soon as the next page would push it past your limit. Because the size is measured on the real saved bytes rather than estimated, each part genuinely fits.

Pick one of the common limits — 25 MB for Gmail, 10 MB for many corporate servers — or type your own. You get a list of parts with their page ranges and exact sizes, each with its own download button. All of it happens in your browser.

Frequently asked questions

How do I split a PDF to fit an email attachment limit?

Set the limit to your provider's cap — 25 MB for Gmail, often 10 MB for corporate servers — and split. Each part is checked against that limit after it is saved, so you can attach them without a bounce.

Why is one of my parts still over the limit?

Because a single page on its own is bigger than the limit, and a page cannot be broken in half. Run the file through a PDF compressor first, or raise the limit if you can.

Do the parts overlap or lose pages?

No. Pages are distributed in order with no duplicates and none dropped, so concatenating the parts in order reproduces the original page sequence exactly.

Why not just split by page count?

Page sizes vary hugely — a page of text might be 20 KB and a scanned photo page 3 MB. Splitting by count gives you parts of wildly different sizes, some still too big.

Would compressing the PDF be better than splitting it?

Often, yes — try compressing first if quality allows, since one file is easier for the recipient. Split when the document must stay at full quality or is simply too large to compress under the cap.

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