How to Split and Merge PDF Files, Reorder, Rotate and Delete Pages

Most PDF chores come down to five page jobs: pull some pages out, combine several files, put pages in the right order, turn sideways pages upright and drop the pages nobody needs. This guide shows how to split and merge PDF files and handle the other three jobs, with the exact page range syntax, a fix for scans that come out in the wrong order, and a table of what each operation keeps and drops. Every tool mentioned here runs in your browser, so your documents never leave your device.

How to split and merge PDF files without uploading them

Contracts, medical letters and bank statements are exactly the files you should think twice about sending to a server just to cut them in half. The page tools on FormatterHQ read the PDF with JavaScript inside the page, copy the pages you choose into a new file in memory and hand you the result as a download.

Each job has its own tool: Split PDF, Merge PDF, Organize PDF for reordering, Rotate PDF and Delete PDF Pages.

Splitting a PDF: every page, every N pages or custom ranges

Split PDF offers three modes. Every page gives you one single-page file per page, which suits a batch of scanned receipts. Every N pages cuts the document into equal chunks; the last chunk simply holds whatever is left. A 10-page file split every 4 pages gives three files: pages 1–4, 5–8 and 9–10.

Worked example: the custom range syntax

Custom ranges is the mode you will use most. Each comma-separated item becomes one output file, and each item can be a single page or a range. Suppose you have a 24-page annual report and want the cover, the main report, the financial tables and the appendix as separate files:

1, 2-15, 16-21, 22-

The open-ended form 22- is handy because you do not need to know the page count. Ranges may overlap, so 1-5, 1-10 produces two files that both start with page 1. You can download the parts one by one or all together as a ZIP.

Two side effects are worth knowing. Fonts and images that the original shared between pages are copied into every part that uses them, so the parts together can be larger than the original. And a link that pointed to a page now sitting in a different part is removed, because its target no longer exists in that file. The parts carry no document properties, so an old title or author name does not travel with them.

Merging PDFs: order, page counts and mixed page sizes

To merge, add two or more PDFs and arrange them with the arrow buttons. Each file is checked as soon as you add it: you see its page count and size, and a damaged or encrypted file is marked in red so you can remove it before merging rather than discovering the problem at the end. The running total, such as 3 files · 27 pages, is a quick sanity check that nothing is missing.

Pages are copied as they are. Text stays text, images are not recompressed, and links within each original file keep working in the merged one. The merged file starts with clean document properties, so it does not inherit the title or author of whichever file happened to come first.

Mixed page sizes are fine. Every page in a PDF has its own size, so an A4 letter merged with a US Letter invoice and a landscape spreadsheet keeps each page exactly as it was. If you need everything on one paper size when printing, use your print dialog's fit-to-page or scaling option rather than changing the PDF.

Reordering pages, including back-to-front and duplex scans

Organize PDF shows every page as a thumbnail. Drag a page to its new position or use the arrows under it to move it one step at a time. Reverse order flips the whole document in one click, which fixes a stack that was scanned face down, and Reset returns to the original order. Links follow their pages, so a table of contents link still lands on the right page after you move it.

Fixing an interleaved duplex scan

A scanner with a single-sided feeder often leads to this workflow: scan all the fronts, flip the stack, then scan all the backs. On many feeders the backs come out in reverse order. For a 5-sheet, 10-page document you end up with two files:

fronts.pdf  pages 1, 3, 5, 7, 9
backs.pdf   pages 10, 8, 6, 4, 2

1. Open backs.pdf in Organize PDF, click Reverse order and download it. It now reads 2, 4, 6, 8, 10.
2. Merge fronts.pdf and the reversed backs, fronts first. The result reads 1, 3, 5, 7, 9, 2, 4, 6, 8, 10.
3. Open the merged file in Organize PDF and drag each even page after its odd partner: 2 after 1, 4 after 3, and so on.

For long documents, check whether your scanning software has a duplex or collate option first.

Rotating pages losslessly

Every PDF page can carry a /Rotate value, a multiple of 90 degrees that tells viewers how to display it. Rotate PDF changes only that value. Nothing on the page is re-rendered or recompressed, so a scanned page keeps its exact image quality and the file size barely changes.

You can rotate single pages with the arrows under each thumbnail, or turn every page left, right or 180° at once. Rotation is added to whatever the page already has, so rotating a page that is already set to 90° by another 90° gives 180°. Because the rest of the file is left alone, rotation is the one page job that keeps bookmarks, links, form fields and document properties.

Deleting pages so they are really gone

The PDF format allows an editor to save changes as an incremental update: instead of rewriting the file, it appends the changes to the end. Some editors save this way. When a page is deleted in an incremental save, it is removed from the page list, but its text and images can still sit in the earlier part of the file. Anyone who inspects the raw file or recovers the earlier revision may be able to read it.

Delete PDF Pages avoids that by building a brand-new file from the pages you keep. Click thumbnails to mark pages, or type numbers such as 2, 5-7. Links that pointed to a deleted page are removed, so they cannot pull the deleted page back into the new file as a hidden object. The title, author and other properties are kept. At least one page has to stay.

What each operation keeps and drops

If a long manual depends on its bookmark panel, plan to add bookmarks again in a PDF editor after splitting or merging. If a fillable form matters, keep the original file for filling and signing, and use the page tools on copies you only need to read or print.

Why encrypted PDFs are refused

An encrypted PDF either needs a password to open or has an owner password that restricts printing, copying or editing. Files with only an owner password open without a prompt in most viewers, so they are easy to mistake for ordinary PDFs.

Saving a changed copy of an encrypted file would quietly remove its password protection, which is exactly what the person who protected it did not want. So the page tools refuse encrypted PDFs instead of producing an unprotected copy, and Merge PDF flags them in red when you add them. If you are entitled to change the file, remove the password in the app that created it, do the page job, and protect the result again if it still needs protection.

A quick order of work for messy documents

When a scanned bundle needs several fixes, this order avoids redoing work:

1. Merge the separate scans into one file.
2. Reorder the pages, using Reverse order for back-to-front stacks.
3. Delete blank separator pages and duplicates.
4. Rotate any sideways pages.
5. Split the clean file into the parts you need to send.

Keep the original files until you have checked the final result page by page.