Splitting or extracting
The two get confused often. Split PDF breaks one document into several new files, for instance an annual report into twelve monthly ones. Extract pages instead pulls out individual pages and saves them as one new document.
As a rule: if you want to send something, you usually need extracting. If you want to tidy up an unwieldy collection, splitting is right.
The most common case
Somebody asks for the March invoice and you have a file covering the whole year. Instead of sending everything, you pull out the two pages that belong to it. That is faster for the recipient and you disclose nothing that is none of their business.
What gets overlooked when sending
A PDF carries more than what is printed on its pages. Author, the program used, creation date and sometimes the full path on your machine sit in the metadata. For an internal document that hardly matters, for one going outside it sometimes does. Remove metadata clears those entries.
Pages nobody should see
If only one paragraph on a page is a problem, deleting the whole page is the wrong answer. For individual passages there is redaction. One thing matters here: a black rectangle drawn on top in an image editor only hides the text visually. It can still be selected and copied. Proper redaction removes the text from the file.
Order no longer right
After splitting and reassembling, pages occasionally end up in the wrong place. Organize pages sorts that out: you see every page as a thumbnail and drag it where it belongs.
Finding the right pages
In a three hundred page document the question is not how to split but where. Going through Organize pages helps: every page sits there as a thumbnail, and chapter openings or invoice headers are visible at a glance. Only once you know the page numbers is extracting worth starting.
For recurring documents with a fixed structure, bank statements running two pages per month for instance, splitting into equal chunks is the faster route.
Three cases from practice
The accountant asks for individual receipts. Instead of sending the whole folder you pull out the pages concerned. That saves follow up questions and you keep track of what left the building.
A contract with appendices. The other side needs the contract, not your internal costing in the annex. Extracting here is not just convenient, it is a matter of care.
A manual where only one chapter is needed. Sending thirty pages instead of four hundred gets you an answer sooner.
What to check after splitting
Open the new file and look at the first and last page. Splitting at an awkward point occasionally cuts off the start of a paragraph or the footer carrying the reference number. Both are noticed by the recipient, not by you.
Check as well whether the page numbers in the new document still make sense. An extract starting at page 47 looks unfinished. Adding page numbers lets you set the count afresh.
Common questions
Does quality suffer? No. Splitting copies pages, it does not recalculate them. Text and images are identical afterwards.
Are bookmarks and links lost? References pointing to a page outside the new document lead nowhere. In a manual full of cross references the extract's table of contents is worth a look.
Can I split a password protected PDF? Only after entering the key. Unlock PDF can lift the protection first, provided the document is yours.