How to combine PDF files in the correct order

Prepare the files first

1. Rename files with numbers such as 01-cover, 02-report, and 03-appendix if their order is not obvious.
2. Open each PDF and remove accidental blank pages or duplicate scans.
3. Keep originals in a separate folder until the combined PDF has been checked.

Merge and verify

Add the PDFs in the order in which they should appear. After the new file downloads, check the first page, every transition between source files, and the final page. This catches most ordering mistakes without reviewing every line.

For a document that will be printed, also check page orientation. A sideways scan can make an otherwise correct combined file inconvenient to use.

Use a clear filename

Choose a filename that explains the document, version, and date, for example project-report-final-2026-07.pdf. Avoid names such as merged-final-final2.pdf, which become difficult to identify later.