How to split a large PDF into parts under a size limit
Open Split by size, add the big PDF, pick the most each part may be, 5, 10 or 25 MB or another size, and press Split into parts that fit. You get as few parts as possible, each under the limit, with the pages in order.
Split by sizeFree. Nothing is uploaded.
How to do it
- Open Split by size and add the PDF.
- Choose 5 MB, 10 MB or 25 MB, or Another size and type the megabytes.
- Press Split into parts that fit.
- Read each part’s size and pages in the result.
- Save the parts, or use Save all, and upload or send them in order.
When splitting beats compressing
Compressing makes one smaller file, but it softens photos, and a long scan may not fit a limit however hard it is squeezed. Splitting leaves every page exactly as it was and shares the pages out between files. It is the right choice when a portal or an inbox takes several files but caps each one: an insurance claim with a long hospital record, a tender with its drawings, a scanned property file.
If the place you are sending to takes only one file, Compress is the tool instead; see compress a PDF to 1 MB.
How the parts are made
Each part is made as big as it can be while staying under your limit, so you get as few parts as possible. They are rarely equal. The tool saves each candidate part and measures it rather than guessing, because fonts and pictures shared between pages are copied into every part that uses them: ten pages of a 50 MB file are seldom a fifth of it. A part of photos may hold a few pages, and a part of typed text hundreds.
Here 1 MB is 1,000,000 bytes, slightly less than some programs count, so a part made under 10 MB is under 10 MB wherever it is checked.
Pages bigger than the limit
A single page can be bigger than the limit on its own, such as a high-resolution scan of a map or a site plan. It cannot be split further, so it becomes a part by itself, and the result line says it is bigger than the limit. Save that part, open Compress, add it alone and choose To a size, then send it with the others.
Choosing the size
Use the limit the portal or email states, as it is: the parts are already measured safely under it. For email, remember that the person receiving may have a lower limit than you, and 5 MB is safe for almost any inbox. Another size takes anything from 1 MB to 1,000 MB; a limit written in KB is the same number divided by 1,000, so 2,000 KB is 2 MB. For limits under 1 MB, split by pages with Split and compress the parts instead.
Sending the parts
Parts are named part 1, part 2 and so on, in page order, and the result gives each one’s size and the pages it holds. Upload them in that order, and if a portal lets you name each upload, use the pages: Hospital record, pages 1 to 46. By email, say in each message which part it is and how many there are. The person receiving can put them back together with Merge.
A worked example
Farah has a 62 MB scan of her father’s hospital records for an insurance claim, and the claim portal takes several files of up to 10 MB each. She opens Split by size, adds the scan, leaves 10 MB chosen and presses Split into parts that fit. The parts come back each under 10 MB, with their pages listed, and she uploads them in order, part 1 first. Had the portal taken only one file, she would have compressed instead, and checked that the doctors’ notes still read clearly.
Questions people ask
Are the pages changed or compressed?
No. Pages are only shared out between the parts, in order, exactly as they were.
Can I choose the number of parts instead?
Not here. For a set number of pages in each part, use Split with Every few pages.
My file is already under the limit. What happens?
Nothing is split, and the result says the file is already under that size.
Is my file uploaded to be split?
No. It is split in your browser, on your device. The only place the parts go is wherever you send them.
Does a locked PDF give locked parts?
Yes, each with the same password. Unlock it first with Remove a password if the person receiving should not need it.
Your file stays on your device. Foolscap does the work inside your browser, so nothing is uploaded and there is nothing for anyone to keep. How you can check