Add Page Numbers always embeds a subset of DejaVu Sans for the printed label, with no font-choice control in the form.
Adobe's own Acrobat documentation for headers and footers describes a Font section where a user adjusts the font type, size, and color of the inserted text. Add headers and footers to PDFs in Acrobat
Add Page NumbersChange Page Number Font Size PDF
The label is always rendered at a fixed size of 11 points regardless of page dimensions.
Upload the file to begin the page-numbering process.
Select the position for the page number label.
Add Page Numbers also fixes the margin around the label at 24 points, with no control to move it closer to or farther from the page edge.
Download the resulting PDF to review the fixed DejaVu Sans styling.
Using Desktop Software for Custom Fonts
Open the document in Adobe Acrobat desktop software.
Navigate to the header and footer editing tools.
Adjust the font type, size, and color in the Font section.
Apply the changes to the selected pages.
Continue with Add Page Numbers to Rotated Pages or Page X of Y Format.
Frequently Asked Questions about Change Page Number Font Size PDF
How do I upload a PDF to add page numbers?
Upload the PDF file using the link below.
Where do I select the page number position?
Select the position dropdown in the form before processing.
How do I download the finished document?
Download the finished PDF from the results screen.
Where do I find font options in desktop software?
Open the Font section in the header and footer dialog.