What graph paper is good for
In math class, grid paper keeps columns of numbers aligned for long division and multiplication, and makes it easy to draw axes, plot points and sketch functions. In geometry, it helps with shapes, areas and symmetry. Science students use it to chart results of experiments by hand.
Outside school it is just as handy: sketching a floor plan or a garden layout, planning furniture in a room, designing knitting, cross-stitch and embroidery patterns, drawing pixel art, mapping a tabletop game, planning a quilt, or making a habit tracker and a simple chart for a bullet journal.
Choosing the square size
Squares go from 4 to 10 mm. Small squares of 4 or 5 mm fit more detail on a page and are common for math notebooks and technical sketches. Medium squares around 6 or 7 mm are easier to write numbers in. Large squares of 8 to 10 mm suit younger students, large handwriting, and patterns where each square must be colored in clearly.
If you need the reference to inches, keep in mind that the spacing here is set in millimeters. For very fine measurements, millimeter paper adds 1 mm squares with stronger lines every 5 and 10 mm.
Print at actual size
For a 5 mm square to really measure 5 mm, print the PDF at 100% scale, or "actual size". With "fit to page" turned on, the printer shrinks the page slightly and the grid no longer matches real measurements, which matters if you draw to scale. Choose Letter in the United States and Canada, A4 in most other countries, or Legal for longer pages.
Gray lines stay in the background and save ink. Blue is classic for notebooks. Black is best if you will photocopy the sheets or need strong contrast.
Free and private
The PDF is created in your browser, with no account and no watermark, and nothing is sent anywhere. Make from 1 to 10 pages at once and print the file as often as you like. The same tool also makes lined, millimeter, dot, isometric, staff and calligraphy paper.
Teachers can prepare a stack for a math unit in a minute, with the name and date line turned on so every sheet is ready to hand in. At home, a few sheets on the desk are enough for homework, quick sketches and plans. Because it is a regular PDF, you can keep the file and print another copy at any time, at home or at a copy shop.