US 1 Knitting Needle: Metric & UK Size

US 1 converts to 2.25mm metric, and to UK/Canada (old) size 13. It sits right at the top edge of lace weight's recommended range (US 000-1) and the bottom edge of fingering weight's (US 1-3), making it one of the more genuinely dual-purpose small sizes.

What it's typically used for

Fine shawls, baby garments in fingering weight, and the first needle size many sock knitters reach for before sizing up or down based on their swatch. Because it straddles two weight categories' recommended ranges, US 1 is also a common "in-between" choice for a knitter whose gauge runs loose on the standard fingering-weight needle size (US 2-3) and needs a finer tool to match a pattern.

Its place in the wider table

US 0 (2.0mm, UK 14) sits one step finer; US 1.5 (2.5mm) sits one step up, with no UK old number of its own. That US 1 to US 1.5 to US 2 stretch uses half-size increments not found elsewhere at the small end of the range — gauge sensitivity matters enough at fine weights that even a quarter-millimetre needle change can meaningfully shift stitches per inch.

Gauge implications

Fingering yarn's published range runs 27-32 stitches per 4 inches, and a US 1 needle tends to land toward the tight, dense side of it — plenty of knitters find they need to move up to a US 2 or 3 to hit a fingering-weight pattern's stated numbers, leaving US 1 as more of a "knits loose" fallback than a default starting point.

FAQ

Should I start swatching at US 1 for a fingering-weight sock pattern? Most sock patterns suggest a slightly larger starting point (US 1-3) and let your own swatch tell you which specific size within that range to settle on — US 1 is a reasonable choice if you already know your knitting tends to run loose.

Is US 1 too fine for a beginner? It's more fiddly than a mid-range worsted needle, but not inherently harder — the main practical challenge is simply that stitches are smaller and slower to see clearly while learning, not that the technique itself changes.

What's the closest crochet hook equivalent to a US 1 knitting needle? Roughly a C-2 (2.75mm) or D-3 (3.25mm) hook by raw diameter, though knit and crochet gauge at "matching" tool sizes don't produce directly comparable fabric — see the Needle & Hook Size Converter for the full comparison.