Crochet chart paper
Crochet chart paper proportioned for crochet rather than knitting — crochet stitches are taller relative to their width, and the ratio changes dramatically with the stitch you are working.
Opens with these settings already loaded. Change anything you like, then download as PDF, PNG or SVG.
Crochet gauge is not one number
Knitting has a fairly stable stitch-to-row ratio, so one chart shape covers most of it. Crochet does not. Single crochet is roughly square, often a little taller than wide. Half double is noticeably taller. Double crochet can be twice as tall as it is wide. Charting all three on the same grid guarantees at least two come out distorted, which is why a single "crochet graph paper" download cannot be right for everyone.
Working out your ratio
Make a swatch in the stitch you are actually using, count stitches and rows over four inches, and divide stitches per inch by rows per inch. Single crochet at 14 stitches and 16 rows per four inches gives 14 ÷ 16 = 0.88 — but enter it as rows-over-stitches for cell height, so around 1.15 for a taller cell. The generator takes cell height as a multiple of cell width, so a value above 1 makes cells taller than wide, which is what most crochet needs.
Tapestry crochet and graphgans
Colourwork charts — tapestry crochet, intarsia, graphgan blankets — are where this matters most, because you are drawing a picture and any gauge mismatch stretches or squashes it. If your blanket looks right on the chart and wrong in yarn, the chart proportion is almost always the culprit rather than your stitching.
Crochet in the round
Amigurumi and mandalas worked in rounds do not sit on a rectangular grid at all — stitch counts increase each round, so the natural chart is radial. The polar sheet is a reasonable starting point for those, with each ring a round, though you will be spacing stitches by eye rather than by cell.
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.