Your thesis is exported, formatted, and the figures finally sit where you put them. Then you notice the pagination is wrong — the numbering restarts at the appendix, or the front matter is numbered when it should not be, or the submission guidelines want numbers bottom-centre and yours are top-right.
Going back to Word and re-exporting is the obvious move and frequently the wrong one, because in a long document with embedded figures and equations, re-exporting is how the layout shifts and something that was fine last week suddenly is not.
Numbering the PDF directly
The numbers are drawn into the pages, so they behave like any other page content — they print, they survive being merged into another document, and they display identically everywhere.
The file is processed in your browser, which matters for unpublished research.
Skipping the front matter
Almost every university requires that the title page is not numbered, and often that the abstract and acknowledgements are not either. Set the tool to start numbering after those pages.
The question that follows is whether the first numbered page should read "1" or continue the count including the skipped pages. Check your institution's guidelines — both conventions exist:
If your guidelines specify roman numerals for front matter and arabic for the body, that is a two-pass job: split the document, number each part appropriately, then merge it back together.
Position and margins
Standard placements, and when each is expected:
Watch the margin. If your document is bound, the inside margin is wider than the outside one, and a number placed at a fixed distance from the edge sits visually off-centre once bound. If your guidelines specify a binding margin, allow for it.
Also check the number does not land on existing content. Long tables and full-page figures often run close to the bottom of the page, and a page number dropped on top of a table row is worse than no page number.
Check these pages specifically
After numbering, open the file and inspect:
The first numbered page. Confirm it is the page your guidelines say it should be, with the number they specify.
Every landscape page. Rotated pages are where numbering goes wrong most often — the number may end up rotated with the page, or in a position that reads oddly.
Full-page figures and tables. Look for collisions with existing content.
The last page. Confirm the count ends where you expect. An off-by-one here usually means front matter was miscounted.
If you have to renumber
Numbers drawn into a PDF cannot be edited afterwards — they are page content now, not a field. If you get the settings wrong, go back to the un-numbered original and do it again. Keep that original until the submission is accepted.
That is a genuine argument for getting pagination right in Word before exporting, where it stays editable. The PDF route is the pragmatic answer when re-exporting risks disturbing a layout you have already fought with.