How do I keep the cover or letterhead page at the start of every part after splitting a PDF?

A comma and a space do not mean the same thing

That is the whole trick. In “One PDF per range” a comma ends one file and starts the next. A space inside a group means more pages for the same file. So 1 2-10 says: one file with page 1 and pages 2 to 10. A comma followed by 1 11-20 then starts a second file with page 1 again and pages 11 to 20.

Repeating a page in more than one file is allowed in this mode, because each group is handled on its own.

The steps

1. Open Split PDF and choose the file, say a 20-page guide whose first page carries your logo and contact details.
2. Choose “One PDF per range”.
3. Type: 1 2-10, 1 11-20
4. Check the preview line: a ZIP with 2 files and 21 pages in total, because the cover is counted twice.
5. Press “Split and download”.

More than two parts

Repeat page 1 at the start of every group. For a 30-page quotation pack you want in three parts, type 1 2-10, 1 11-20, 1 21-30. If the letterhead is two pages, such as a cover and an about page, type 1-2 3-10, 1-2 11-20.

When you do need the merge tool

The ascending rule helps when the shared page sits at the front of the original. But if you want a shared closing page, such as terms and conditions, at the end of every part and it is page 2 of the original, splitting cannot put it last, because page 2 will always come before page 11. Instead, extract the terms page on its own, split the parts, then join each part with the terms page in the order you want using Merge PDFs.

• If the shared page is at the end of the original, such as page 20, the ascending rule puts it last in every part automatically: 2-10 20, 11-19 20.
• Check the first and last page of every output before sending.