Split PDF by Size
Split a PDF into consecutive parts that each stay under a target file size — ready for email and upload limits.
About this tool
The limit is never the document — it is the channel: 25 MB for an email, 10 MB for a portal, less for a chat app. This tool walks the pages in order and packs them into consecutive parts, each saved part kept under the target size you set, so every part is individually sendable.
A single page that is already larger than the target cannot be split by packing; it becomes its own part and the result card says so openly. Parts are numbered, and together they contain the whole document in order.
How to use Split PDF by Size
- Choose exactly one PDF file.
- Set the maximum size per part, in MB.
- Download each part in order.
Keep the original files and inspect the exported result before publishing or sharing it.
Frequently asked questions
How are the parts built?
Pages are added one at a time until the next page would exceed your target; then a new part begins. Page order is preserved.
What if one page alone is bigger than the target?
That page becomes a part of its own and will exceed the target — it cannot be split further without re-encoding its content.
Why split by size?
Email attachments (25 MB), upload portals and messaging limits all cap file size; this keeps every part sendable.
Are encrypted PDFs supported?
No. Encrypted or password-protected PDFs are rejected. Export an unlocked copy first.
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