Yarn Weight & Knitting Needle Size Converter

Why knit gauge differs from crochet gauge at the same weight

The same skein of worsted-weight yarn produces a looser, more open fabric in stockinette than it does in single crochet, because a knit stitch and a crochet stitch use a different amount of yarn to cover the same area. That's why a knitting needle chart and a crochet hook chart show different gauge numbers for identical yarn weight categories — it isn't inconsistency between the charts, it's a real structural difference between the two crafts. If you're checking whether a "worsted weight, gauge 18 sts" pattern is knit or crochet, the gauge number itself is often the giveaway: crochet gauge at that weight typically runs tighter (more stitches per 4 inches) than knit.

Circular vs straight needles

The millimeter size is what determines gauge, not whether the needle is straight, circular, or double-pointed — a US 8 straight needle and a US 8 circular needle produce identical stitches. Circulars are worth using even for flat (back-and-forth) knitting once a project gets wide, simply because the cable holds the weight of a large piece more comfortably than two straight needles, not because it changes the fabric.

When a yarn's label disagrees with this chart

Treat the yarn label's own suggested needle size as more reliable than a general chart whenever the two disagree — the manufacturer tested that specific yarn, while a weight-category chart is an average across many different yarns that happen to share a category. This chart is most useful for yarns with no needle recommendation printed on the label at all, or as a sanity check before buying needles for a project.