Five squares per inch graph paper
Fifths of an inch, with a heavier line every fifth square so the inch divisions stay readable.
Opens with these settings already loaded. Change anything you like, then download as PDF, PNG or SVG.
Between quad ruled and engineering paper
US graph paper clusters around a few rulings. Quad ruled means four squares to the inch and is what most school pads use. Five to the inch is a step finer and tends to be preferred once the work gets denser, in high school and college math and science. Ten to the inch is engineering paper, fine enough for decimal work and too fine for comfortable freehand plotting.
Fifths make decimal arithmetic easy
Each square is 0.2 inches, so five squares is exactly one inch and the heavy line falls on every inch. That matters when you are plotting decimal data on an inch scale, because one square is two tenths and you never have to divide by four in your head. Quarter-inch paper is friendlier for fractions and worse for decimals, which is roughly the split between the two rulings.
A note on what a printed square is worth
This only helps if the sheet prints at the size it claims. Print dialogs default to shrinking the page to fit the printable area, typically by a few percent, and a 0.2 inch square that arrives at 0.19 is worse than useless for measured work because it looks right. The calibration page settles it in one sheet, and the explanation of why it happens is here.
Printing it accurately
This only measures correctly if your printer doesn't rescale the page. In the print dialog set Scale: 100%, not "Fit to page" or "Shrink oversized pages". If you're not sure it worked, print the calibration page, measure the ruler on it with a real ruler, and it will tell you exactly what your printer is doing to the page.