Printable graph paper

The one thing that matters here is printing at 100%. Print dialogs default to "fit to page" or "shrink oversized pages", and either will scale the sheet by a few per cent — which makes 5 mm squares come out at 4.8 mm and quietly ruins the point of graph paper. Turn scaling off, and check the first sheet with a ruler before printing fifty.

The grid is centred on the printable area rather than started at the margin, so the border is even on all four sides. Started from one corner, a grid leaves whatever does not divide evenly as an uneven strip along the opposite edge, which looks like a mistake even though the squares are correct.

The standard sizes are worth knowing: 5 mm is the usual school maths paper, 1 cm for graphs and rough plotting, 2 mm for detailed technical work, and 1/4 inch (6.35 mm) is the American equivalent of 5 mm. Dot grid at 5 mm is the bullet-journal standard and is easier to write over than a full grid, because the dots disappear behind ink rather than showing through it.

An honest note on ink: a full square grid across a page uses a surprising amount of toner. Dot grid uses a fraction of it and works just as well for most purposes.