5 mm, 1 cm or Quarter Inch? Choosing a Graph Paper Grid Size
5 mm is the European school standard, quarter inch is the US one, and they are 27% apart. Here is how to pick without guessing.
2 October 2026 · 6 min read · Printing
Grid size decides how much fits on a page and how fine your work can be. The common sizes exist for good reasons, and they split neatly along the metric and imperial line.
The sizes people actually use
| Grid | In the other system | Typical use |
|---|---|---|
| 2 mm | 0.079 in | Lab plotting, fine detail |
| 2.5 mm | 0.098 in | Engineering pads, 4 to the centimetre |
| 5 mm | 0.197 in | European school and engineering standard |
| 1 cm | 0.394 in | Primary school, rough plans |
| 1/10 in (2.54 mm) | 2.54 mm | US engineering and survey work |
| 1/4 in (6.35 mm) | 6.35 mm | US classroom standard |
| 1/2 in (12.7 mm) | 12.7 mm | Early years, large layouts |
5 mm and quarter inch are not interchangeable. A quarter inch is 6.35 mm, 27% larger, so a drawing counted in squares will come out a quarter bigger than intended if you swap them. Convert properly with the inches to centimetres converter when a drawing has to move between systems.
Pick by what you are doing
School maths. 5 mm with a darker line every centimetre in most of the world; quarter inch in the US. The emphasis lines matter more than the size — they stop you losing count.
Graphing functions. 5 mm, with bold lines every 10 squares so each major division is 5 cm. Axes land on bold lines and stay readable.
Engineering sketches. 2.5 mm or 1/10 inch with strong major lines. Fine enough to dimension, coarse enough to read at arm's length.
Scale drawing. Choose the grid to match the scale. At 1:50, one 5 mm square is 25 cm of real building; at 1:100 it is 50 cm. Rooms then land on whole squares, which is the entire point.
Bullet journals. 5 mm dot grid, because that is what Leuchtturm, Rhodia and Moleskine all use — spreads you copy from the internet will line up.
Knitting and cross-stitch. Use a grid that matches your gauge rather than a square one, since stitches are wider than they are tall. A 1 cm grid is a reasonable starting point for charting.
Children learning to write numbers. 1 cm or 1/2 inch. One digit per box, with room for wobble.
How many squares fit a page
On A4 with a 10 mm margin, the drawable area is 190 × 277 mm:
| Grid | Squares across | Squares down |
|---|---|---|
| 2 mm | 95 | 138 |
| 5 mm | 38 | 55 |
| 1 cm | 19 | 27 |
| 1/4 in | 29 | 43 |
A3 doubles the area, which is often the better answer for a drawing that will not fit rather than dropping to a finer grid.
Line weight and colour matter too
A 0.18 mm grey grid sits behind your work. A 0.4 mm black grid competes with it. Light blue is the traditional choice for drafting because it photocopies and scans away almost completely, leaving only your pencil lines — useful if the sheet gets digitised. All of this is adjustable in the generator.
Related
This article is for general information. Please verify figures against the relevant standard before using them in critical work. About accuracy