How to Split a Large PDF for an Upload Limit

Most PDF splitters, including ours, split by page — you choose where the breaks go, and each resulting file contains a specific range of pages. That's slightly different from the problem of "this 80MB file won't fit under this portal's 10MB limit," where you don't care about page numbers at all, only about getting under a size cap.

Figure out why it's so large first

Before splitting anything, check whether the file is large because it's genuinely long, or because a handful of image-heavy scanned pages are bloating an otherwise normal document. If it's the latter, Compress PDF alone — targeting a specific size — might solve the problem without splitting anything at all. See our guide to compressing a PDF for email for the same idea applied to attachment limits.

A workflow that reliably hits a size target

1. Compress the full document first, if it hasn't been already.
2. If it's still too large, split it into roughly equal page ranges with Split PDF — halves, thirds, or however many pieces get each chunk comfortably under the limit.
3. Check each resulting file's size individually — an uneven document (a few pages with lots of images, the rest plain text) can split unevenly even with equal page counts.
4. Compress any chunk that's still over the limit on its own.

Keep the pieces in order

Once a document becomes several files, filenames are the only thing telling you their order. Number them clearly (part-1, part-2, and so on) before sending or uploading them, especially if they're going somewhere that will display them alphabetically rather than in upload order.