US Size 6 Knitting Needles (4 mm): Yarn Weight, Gauge and Conversions
A US size 6 knitting needle is 4 mm in diameter, old UK and Canadian size 8. It suits light (DK) yarn, which knits at 21 to 24 stitches per 4 inches. At about 23 stitches per 4 inches, a 20 inch hat needs about 116 stitches and an 8 inch scarf about 46.
Knitting needle size is the diameter of the shaft, measured in millimeters. This needle is 4 mm, about 0.16 inch across. US size 6 is the American label for a 4 mm needle, and old UK and Canadian size 8 is the same needle. The millimeter figure is the one that matches across every brand, so it is printed on most needles and needle gauges.
What is a US 6 knitting needle in mm and old UK sizes?
| Metric | 4 mm |
|---|---|
| Inches (diameter) | 0.16 in |
| US size | 6 |
| Old UK and Canadian size | 8 |
| Crochet hook, same diameter | G-6 (4 mm) |
| Usual yarn weight | light (DK) |
| Estimated gauge | about 23 stitches per 4 in |
Some charts also list the sizes below. They are close enough to 4 mm that they share this page.
| Metric | US | Old UK | Note |
|---|---|---|---|
| 4.25 mm | 6 | None | Less common; listed on the CYC chart. |
What yarn weight goes with US 6 needles?
The Craft Yarn Council lists 4 mm inside the recommended needle range for the yarn weights below. The hat and scarf columns show how many stitches the full gauge range of each weight gives, so you can see how much the yarn choice moves the numbers.
| Yarn weight | CYC needle range | Gauge per 4 in | 20 in hat | 8 in scarf |
|---|---|---|---|---|
| Light (DK) | 3.75 to 4.5 mm (US 5 to 7) | 21 to 24 | 104 to 120 | 42 to 48 |
How many stitches do you cast on with US 6 needles?
The estimated gauge places 4 mm within the CYC range for light (DK) yarn: the smallest recommended needle gets the most stitches per 4 inches and the largest gets the fewest. That gives about 23 stitches per 4 inches on this needle. Circular pieces are rounded to a multiple of 4 so 2x2 ribbing works out.
| Piece | Width or circumference | Cast on (estimate) |
|---|---|---|
| Hat, 20 in around (multiple of 4) | 20 in | about 116 |
| Snug hat, 18 in around | 18 in | about 104 |
| Cowl, 24 in around | 24 in | about 140 |
| Scarf, 8 in wide | 8 in | about 46 |
| Baby blanket, 42 in wide | 42 in | about 242 |
| Throw, 50 in wide | 50 in | about 288 |
Swatch before you trust any cast-on number
Knit a swatch at least 6 inches wide, wash and dry it the way you will treat the finished piece, then count stitches across the center 4 inches. Put your real number into the cast-on calculator for an exact count.
Needles and supplies for US 6 (4 mm)
Prym Ergonomics 32-Inch Circular Knitting Needles Set, US 2, 4 and 6
$24.1432 inch circulars in US 2, 4 and 6 with a round tip and a triangular body designed for grip.
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Knit Picks Sunstruck Wood Interchangeable Needle Set, US 4 to 11
$77.47Nine pairs of birch tips from US 4 to 11 (3.5 to 8 mm) with four cables, the budget way to own every mid size.
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Clover Takumi Bamboo Combo Interchangeable Circular Needle Set
$95.59Bamboo tips from US 3 to 15 (3.25 to 10 mm) with five cord lengths for 60 combinations.
Check pricePrices change often, so confirm on Amazon. As an Amazon Associate we earn from qualifying purchases.
What crochet hook matches a US 6 knitting needle?
The G-6 crochet hook is also 4 mm. Diameter is where the match ends, though: crochet fabric is denser, so CYC pairs light (DK) yarn with 3.75 to 4.5 mm (US 5 to 7) needles but larger hooks. A 4 mm hook usually suits a lighter yarn than a 4 mm needle does.
What are the knitting needle sizes next to US 6?
Frequently asked questions
What size is a US 6 knitting needle in mm?
A US size 6 needle is 4 mm in diameter, about 0.16 inch. The old UK and Canadian size is 8. Charts also list 4.25 mm (US 6), covered on this page. US numbers were never fully standardized, so trust the millimeter size printed on the needle or check it in a needle gauge. The neighboring sizes are US 5 (3.75 mm) and US 7 (4.5 mm).
What yarn weight do you use with US size 6 needles?
CYC places 4 mm inside the recommended needle range for light (DK) yarn. Light (DK) is the usual match: its range is 3.75 to 4.5 mm (US 5 to 7), knitting at 21 to 24 stitches per 4 inches. The size sits inside a single category, so it is a straightforward match. Your pattern gauge matters more than the category name.
How many stitches do I cast on for a hat with US 6 needles?
At about 23 stitches per 4 inches, our estimate for light (DK) yarn on 4 mm needles, a 20 inch hat needs about 116 stitches, rounded to a multiple of 4 for ribbing. For a snug fit many patterns size the hat 1 to 2 inches smaller than the head, which is about 104 stitches at 18 inches. The estimate places the needle within the CYC gauge range, so knit a swatch and recount before you cast on.
How many stitches for a scarf on US 6 needles?
Cast on about 46 stitches for an 8 inch wide scarf at 23 stitches per 4 inches. A 6 inch scarf needs about 35 and a 10 inch scarf about 58. Stitch pattern changes both width and yarn: garter stitch used about 46 percent more yarn than stockinette in one test. A quick 4 inch swatch in the stitch you plan to use gives a better count than the label gauge.
What crochet hook is the same size as a US 6 knitting needle?
The G-6 crochet hook is also 4 mm, so the two share a diameter. They are not interchangeable for the same yarn, though. CYC pairs light (DK) yarn with 3.75 to 4.5 mm (US 5 to 7) needles but 4.5 to 5.5 mm (size 7 to I-9) hooks, because crochet fabric is denser. A 4 mm hook usually suits a lighter yarn than a 4 mm needle does.
Are US size 6 needles good for beginners?
They are better as a second or third project. At 4 mm the stitches are small, about 23 to every 4 inches, so a 20 inch hat is 116 stitches around and progress feels slow. Good light helps a great deal, and if fine needles make your hands ache, ergonomic or square needles and short sessions help.
How we research: we compare manufacturer specifications, owner manuals, published standards and recurring themes in verified owner reviews. We do not test products in person, and this is researched guidance, not professional advice. Follow your machine manual and pattern, and take care with rotary cutters, hot irons and needles. As an Amazon Associate we earn from qualifying purchases.