Split by Size
Split by Size cuts a PDF into files that each stay under a size you set, such as 2 MB for an upload form or 10 MB for email. Each file is measured, not estimated, and nothing is uploaded.
- Input
- One PDF and a size limit
- Output
- A ZIP of PDFs, each under the limit
- Runs
- In your browser. The file never leaves your device.
- Cost
- Free. No sign-up, no watermark.
Choose a PDF file
or drop it here
How to split a PDF by file size
Choose a PDF
Select the document that is too big to attach or upload.
Set the largest size
Type the limit and choose MB or KB, for example 2 MB for a form that refuses anything larger.
Download the ZIP
Each file holds consecutive pages and is named for the pages inside. The result tells you how many files there are and which is largest.
Files that really fit under the limit
Measured, not guessed
Each candidate file is built and saved to see its true size, because pages share fonts and images and cannot simply be added up.
Pages stay in order
Every file holds consecutive pages, each as full as it can be before the next page would push it over the limit.
Honest about big pages
A single page larger than your limit cannot be split. It gets a file to itself and the result names it, so you can shrink it with Compress PDF.
Named by pages
Files are numbered and named for their pages, such as report_part_02_pages_15-31.pdf, so they sort and reassemble correctly.
Frequently asked questions
Will every file be under my limit?
Yes, except a page that is over the limit on its own. Sizes are measured on the real files. The exception is listed in the result with its page number and size.
Why are the files together bigger than the original?
A font or image used on several pages is stored again in every file that needs it. That is unavoidable when a document is cut into independent files.
What if I only need it smaller, not in pieces?
Use Compress PDF to shrink images first. A scan that is 40 MB often falls under a limit without being split at all.
Can I split by page count or chapter instead?
Yes. Split PDF cuts every page, a range, or every N pages. Split by Bookmarks cuts at chapters, and Split by Text cuts wherever a word or pattern appears.
How many files can it make?
Up to 500 at a time. A limit that would make more is refused, and the message suggests a larger size.
Is my file uploaded anywhere?
No. Split by Size runs entirely in your browser: the file is opened and processed on your own device and is never sent to our server. More in the privacy policy.
Is Split by Size free to use?
Yes. Split by Size is free, with no account to create and no software to install — open the page in a modern browser and start.