How to split a PDF (and which of the three things you mean)

Splitting a PDF means three different things to three different people, and the tool that does what you want depends entirely on which one you are.

Which one do you want

• Several separate files out of one document — one per chapter, one per invoice, one per page. That is splitting.
• One new file containing only some of the pages, with the rest left behind. That is extracting.
• The same file, minus a few pages you do not want. That is removing.

The distinction sounds pedantic until you have run the wrong one on a 200-page document and got 200 files.

Splitting into separate files

Use this when the document is really several documents that happen to be in one file — a batch of scanned invoices, a bundle of signed forms, a report where each section goes to a different person.

1. 1Open Split PDF and drop your file in.
2. 2Choose one file per page, or type ranges like 1-3, 7, 10-12 to get one file per range.
3. 3Download. Everything comes back as a single ZIP rather than a stack of separate downloads.

Ranges are the option worth knowing about. One file per page is the obvious default and is rarely what anyone actually needs — a 40-page bundle of ten four-page contracts wants four-page ranges, not forty single sheets.

Extracting instead

If what you want is one new PDF holding pages 12 to 18 of a long report, splitting is the wrong shape of answer. Extract Pages gives you exactly that: one document containing the pages you picked, in the order you picked them, with your original untouched.

This is the right tool for lifting a chapter out of a book, one invoice out of a statement, or the two pages of a form someone actually needs to sign. Extract pages from a PDF goes into it properly.

Removing instead

When most of the document is what you want and a few pages are not — a blank final sheet from a scanner, a cover page, an internal appendix — Remove Pages is less work than describing everything you want to keep. Pick the pages to delete from a thumbnail view or type the numbers.

What splitting does to a document

Pages are not as independent as they look, and a few things do not survive being separated. This is true of splitting anywhere, not just here.

• Bookmarks generally do not come across. The outline is a structure attached to the document rather than to its pages, and there is no correct way to cut it in three.
• Links from one page to another break if the target ends up in a different file. There is nowhere for them to point.
• Digital signatures are invalidated. A signature certifies a specific sequence of bytes, and any rewrite changes those bytes — this is the mechanism working, not a fault.
• Form fields belong to the document. A form split across files usually needs rebuilding rather than splitting.
• Page numbers printed on the pages stay as they were, because they are ink. If you need them renumbered, add page numbers to the result afterwards.

Why the pieces do not add up to the original size

Split a 10MB document into ten files and you will often find they total considerably more than 10MB. This surprises people and is not a bug.

A PDF stores each font, each image and each embedded resource once, and every page that uses it points at that one copy. Separate the pages and each new file needs its own copy of everything its pages reference. A font embedded once in the original is now embedded ten times.

If size is why you were splitting in the first place, compressing may get you there in one step instead — reduce PDF file size for email covers what actually shrinks a file and what does not.

Common questions

Can I split by file size instead of by page?

Not directly, because the relationship between pages and bytes is not even — one page with a photograph on it can outweigh fifty pages of text. If the goal is getting under an attachment limit, compressing first and then splitting by ranges gives you far more control than any automatic size split would.

How do I split a PDF in half?

Use two ranges. For a 40-page document, enter 1-20, 21-40 and you get two files. Ranges are more flexible than a halve button and cover the case where the natural break is not the midpoint.

Is there a page limit?

No fixed one. Everything runs in your browser, so the practical limit is your device's memory. Large documents on a phone are where you would notice; a laptop handles several hundred pages comfortably.

Can I put them back together afterwards?

Yes — Merge PDF reassembles them, and Organise Pages lets you rearrange as you go. Splitting and re-merging is a legitimate way to reorder a document, though organising it directly is fewer steps.

Are my files uploaded?

No. The PDF is read and the new files are written inside your browser. Nothing is sent anywhere, which matters rather a lot when the document being split is a bundle of contracts.