Split PDF by Size
Short answer: To split a PDF by size, choose your PDF, set the maximum size per part, and click Split. Pages are grouped so every output file stays under your limit, and your file never leaves your device.
Split a large PDF into smaller files, each under a size limit you choose. Perfect for email attachments, upload limits, and sharing big documents in parts — free, with no signup, and your file never leaves your device.
or drag & drop it here — processed on your device, nothing is uploaded
Maximum size per part
Your split files
| Part | Pages | Size |
|---|
How to split a PDF by size
Choose your PDF and set the maximum size per part — a preset or any custom MB value.
Click Split. Pages are grouped so every output file stays under your limit.
Download each part individually, or grab everything at once as a ZIP.
When is splitting by size useful?
Email providers cap attachments (often 10–25 MB), upload forms reject big files, and messaging apps choke on large documents. Splitting by size guarantees every part fits the limit — no guessing how many pages make 5 MB. It also helps when sharing a long report in instalments or archiving chapters separately. Because each part keeps the original pages' fonts and images, quality is identical to the source.
Frequently asked questions
How do I split a PDF by size?
Upload your PDF, pick a maximum size per part (for example 5 MB), and click Split. The tool groups pages so every output file stays under your limit, then lets you download each part or all parts as one ZIP.
What happens if a single page is bigger than my size limit?
A single page cannot be split further without recompressing it, so it is kept as its own file and flagged with a warning. Use the Compress PDF tool first if you need that page smaller.
Are the split files smaller than the original?
Yes. Each file contains just its own pages, so individual files are much smaller than the original — handy for email attachments with size limits.
Is my PDF uploaded anywhere?
No. The tool runs entirely in your browser with pdf-lib. Your file never leaves your device.
Can I split by a custom size, not just presets?
Yes. Enter any size in MB (from 0.1 MB up to 100 MB) in the custom field, or use the 1 MB, 2 MB, 5 MB, 10 MB and 25 MB presets.
Why TheEditPDF?
Every tool runs entirely in your browser. Your files never leave your device — ideal for confidential legal, financial and business documents.
All tools free forever. No signup, no watermark, no hidden limits. What you see is what you get.
Works on phone, tablet and computer. Open your browser and start.
Files are processed on your device — nothing is uploaded.