What font size and margin should page numbers use so the office printer does not cut them off?
Use a margin of at least 10 to 15 mm and a font size between 9 and 11 points. Many office printers cannot print right to the edge of the sheet and leave a narrow blank strip, and a number placed too close to the edge can be clipped or vanish. A 15 mm margin puts the number's baseline 42.52 points above the bottom of the page, well clear of that strip.
Why a number vanishes on paper when it shows on screen
A screen shows the page right to its last point. A printer grips the sheet by its edges as it feeds it through, so most office printers have an unprintable area near the edges, and its width varies from model to model. Some print drivers deal with this by shrinking the whole page to fit the printable area, so everything comes out slightly smaller. Others simply clip whatever falls in that strip. Either way, a number hugging the edge is the first thing to suffer.
Check your printer's settings or manual for its minimum margin rather than relying on a fixed figure, but 10 mm is a safe distance for most office use, and 15 mm safer still.
The margin in numbers
The margin in PDF page numbering is set in millimetres, from 0 to 100, and is the distance from the page edge to the number's baseline. On an A4 page 595.28 points wide:
- The default 10 mm puts the baseline 28.35 points up.
- 15 mm puts it 42.52 points up.
- With Top selected, the margin is measured from the top edge with room left for the height of the characters, so the top of the number does not touch the edge.
Font size
The tool accepts 6 to 72 points, with 11 as the default. On a printed A4 sheet, 9 to 11 reads comfortably without drawing more attention than the content. Below 8 it gets hard to read once the page is photocopied or photographed. Above 14 it looks like a heading rather than a page number, except in slides shown on a large screen.
A quick way to be sure
- Number the file with a 15 mm margin and size 10, and check the on-screen preview.
- Print a single page and compare it with the screen: is the number complete, and is the distance from the edge what you expected?
- If the number is clipped, raise the margin. If it sits further in than you like, lower it a little.
- If a warning says the number is wider than the available space or the margin is larger than the page, reduce the font size or the margin.
Common questions
Does the margin resize the page content?
No. Here the margin only sets where the number goes; it neither shrinks nor moves the page content.
What if a commercial print shop is printing it?
Print shops often trim the sheets after printing, so ask how much they trim and add extra margin on top of that.