Graph paper, ¼ inch, for A4

Graph paper is worth printing for long multiplication and long division long before anyone plots a graph on it: one digit to a square is what keeps the columns lined up, and a column that drifts is most of what goes wrong in a long sum.

The lines are drawn as hairlines rather than as a printed background, so they come out of the printer as light as they look here and do not compete with a pencil.

The rules are drawn as real strokes at real sizes — not a picture of lines, and not a background tint. That matters more than it sounds: browsers drop background graphics when printing unless the reader has gone looking for the setting, so ruled paper made the obvious way looks perfect on screen and comes out of the printer blank. Put a ruler on this one. It is the size it says it is.

This sheet is set for A4 — 210 × 297 mm. Paper size is not a preference here: sent to a printer loaded with something else, the browser shrinks the page to fit, and a ruling that has been shrunk is no longer the size it was chosen for. So there is a second copy of this sheet, ruled identically and measured for US Letter.