Split PDF by File Size
Divide a PDF Into Parts That Each Fit a Size Limit
Need to use Split PDF by File Size right now?
Meeting a 5MB email attachment limit or an upload cap is easy when the split is based on actual measured output size.
Drop a PDF, or click to browse
Processed locally in your browser — never uploaded
Each single page must individually be under your size limit — a page containing a very large embedded image can't be split smaller than itself.
Features
- Runs entirely in your browser
- Privacy-first — your data is never uploaded
- Real-time, instant results
- 100% free, no sign-up required
- Works on desktop, tablet, and mobile
- No installation needed
Who uses this tool?
About Split PDF by File Size
Many upload forms, email attachments, and submission portals cap file size at a fixed limit — 5MB, 10MB, 25MB — and a large PDF (especially one full of scanned pages or high-resolution images) can easily exceed that. Splitting by a fixed number of pages doesn't reliably solve this, since pages can vary enormously in size depending on their content. This tool splits a PDF by actual file size instead, guaranteeing every resulting part stays under the limit you specify.
It works by building up each output file page-by-page, checking the actual resulting file size after each page is added, and starting a new file the moment adding another page would push the current one over your specified limit. This means the split points are determined by real measured size, not an estimate or a fixed page count, so the guarantee holds even for documents where page sizes vary wildly (a mix of text-only pages and pages with large embedded photos, for example).
Because the size check happens after each page is actually added and saved, this is a genuinely accurate size-based split rather than an approximation — you can trust that every output file, except potentially the last, is as close to your limit as the page boundaries allow without exceeding it.
There's one hard constraint worth knowing upfront: a single page can't be split smaller than itself. If one page's own content pushes it over your size limit even by itself, that page will still be output as its own file exceeding the limit, since there's no way to further subdivide the content within a single page.
How it works
- Upload your PDF. The file loads ready for splitting.
- Set your maximum size per file. Enter the size limit in megabytes for each output part.
- Split and download. Get a ZIP of parts, each kept under your specified size limit.
Examples
Meeting a 5MB email attachment limit
Input
22MB PDF, 5MB limit
Output
ZIP file with several parts (e.g. part-1.pdf through part-5.pdf), each under 5MB