Split PDF by File Size
Split a large PDF into parts under a target size (MB) for email and upload limits. Free and private in your browser.
Get a big PDF under an attachment limit
Mail servers and portals cap attachments at 5, 10, or 25 MB. Instead of compressing quality away, split the document into sequential parts that each stay under your target size. Sizes are estimated per page and verified, all locally in your browser.
What you can do with it
- Email a large scan
- Split a 40 MB scan into parts under 10 MB and send them in order.
- Meet a portal upload cap
- Court, tax, and application portals often enforce per-file limits — split to comply without losing quality.
How to split a PDF by file size
- Open your PDF — it loads locally with no upload.
- Enter the maximum size per part in MB.
- Click Split & download ZIP to save the parts.
Splitting vs compressing for size limits
Compression trades image quality for megabytes; splitting keeps full quality and divides pages across files. For scanned documents that are already compressed, splitting is often the only way under a hard cap. Estimates are computed per page and any part that still exceeds the target is split again automatically.
Why part sizes are estimates
Fonts and images shared across pages must be embedded in every part that uses them, so three 3 MB parts can total more than the 8 MB original. The tool accounts for this by verifying each part after building it.
Related reading and tools
- Compress PDF — Reduce quality/DPI when one smaller file is preferred over parts.
- Split PDF — Split by explicit pages or ranges instead of size.