Super Fine (Fingering / Sock) Yarn Weight Guide
Fingering is CYC category 1, and it does double duty as both a general fine-garment weight and, in its nylon-blended "sock yarn" form, the default choice for hand-knit and hand-crocheted socks specifically. Those two uses share a gauge range but not always the same fibre content, which matters more here than at most other weights.
Gauge
Standard fingering-weight gauge is 27-32 stitches per 4 inches in stockinette (about 6.75-8 stitches per inch) and 21-32 stitches per 4 inches in single crochet — a genuinely wide crochet range, reflecting how much project intent (a dense amigurumi versus an open lacy shawl) shifts actual worked gauge at this weight. Run fingering's own midpoint gauge through the site's standard hat-sized worked example and the estimate is roughly 265 yards, noticeably more than worsted's equivalent hat despite using thinner yarn — finer gauge means more stitches per square inch, and more stitches means more total yarn passing through the fabric.
Recommended needles and hooks
US 1-3 needles (2.25-3.25mm) and B-1 to E-4 crochet hooks (2.25-3.5mm). Sock knitters commonly work slightly tighter than this range on purpose — a denser fabric wears better at the heel and toe, where friction inside a shoe is highest.
Typical put-ups
Fingering-weight yarn is commonly sold in both 50-gram (200-230 yards) and 100-gram (400-460 yards) put-ups, and sock yarn specifically is very often sold in 100-gram skeins sized to yield almost exactly one adult pair with modest leftovers — a deliberate industry convention, not a coincidence.
Why "sock yarn" is a fibre statement, not just a weight
Most sock yarn is fingering weight, but not all fingering weight is sock yarn — the distinction is the nylon content (commonly 20-25%) blended in specifically for abrasion resistance at the heel and toe. A plain fingering-weight wool with no nylon will felt and wear through faster in that use than a genuine sock-blend yarn, even though both sit in the identical CYC gauge category. If a pattern specifies "fingering/sock weight" for an actual sock, check the label for nylon content, not just the weight category.
What fingering weight is good for
Socks (in its nylon-blended form), fine shawls, baby garments, and lightweight adult sweaters where drape matters more than speed of finishing. It sits at a genuine sweet spot between lace's very fine, slow-to-work gauge and sport/DK's faster, sturdier fabric.
How it compares to sport weight
Sport (CYC category 2) is the next weight up, with a noticeably looser stitch gauge and correspondingly faster progress per hour worked. If you're substituting sport for fingering or vice versa without re-swatching, expect the finished piece to run larger or smaller than intended — the two categories don't overlap in their standard gauge ranges at all, unlike some adjacent weight pairs that do share a narrow overlap band.
FAQ
Is fingering weight the same as 4-ply in UK terminology? Roughly, yes — UK "4-ply" describes a similar gauge range to US fingering weight, though the naming conventions come from different traditions (US names describe relative thickness, UK ply-count names describe the historical number of strands twisted together, which doesn't map precisely to gauge on its own).
Can I use fingering weight for a garment other than socks without adding nylon? Yes — nylon content matters specifically for abrasion resistance at points of friction, like a sock heel. A fingering-weight shawl or sweater has no comparable wear point, so a plain wool or wool-blend fingering yarn works fine there.
How many stitches per inch is fingering weight, roughly? About 7-8 stitches per inch in stockinette at standard gauge, though many sock knitters deliberately work denser than that for durability — treat the range as a starting point and measure your own swatch rather than assuming any single number applies to your yarn and needles.