Yarn Weight Chart: 4 Ply, DK, Aran & Worsted Compared
"DK", "8 ply" and "light worsted" are three names for the same yarn. Here's every weight side by side - with what it's for and what we'd knit it in.
Weight is the thickness of the strand, not how heavy the ball is. Find the weight your pattern asks for, check the gauge, and you're most of the way there.
| Weight | Needle | Gauge / 10cm | Good for | Our picks |
|---|---|---|---|---|
| LaceCYC 0 US lace · 1–3 ply · cobweb, thread | 1.5–2.25mmUS 000–1 | 33–40sts≈ 30–40 wpi | Shawls, wraps, fine openwork and delicate lace | Knitting for Olive Soft Silk Mohair · Isager Silk Mohair |
| 4 plyCYC 1 US fingering / sock · super fine · baby | 2.25–3.25mmUS 1–3 | 27–32sts≈ 14 wpi | Socks, shawls, colourwork and fine-gauge garments | A Yarn Story Opus · John Arbon Exmoor Sock |
| SportCYC 2 US sport · fine · 5 ply · baby | 3.25–3.75mmUS 3–5 | 23–26sts≈ 12 wpi | Lightweight but warm garments, baby knits, shawls with body | A Yarn Story Fluff · Spincycle Dyed in the Wool |
| DKCYC 3 US light / light worsted · 8 ply | 3.75–4.5mmUS 5–7 | 21–24sts≈ 11 wpi | The all-rounder - sweaters, cardigans, hats, accessories | The Raw Wool Company DK · Julie Asselin Leizu · Magpie Swanky DK |
| AranCYC 4 US worsted / medium · 10 ply · afghan | 4.5–5.5mmUS 7–9 | 16–20sts≈ 9 wpi | Cosy jumpers, blankets, hats and mittens | A Yarn Story Origin · CaMaRose Snefnug · Spincycle Dream State |
| ChunkyCYC 5 US bulky · 12 ply · craft, rug | 5.5–8mmUS 9–11 | 12–15sts≈ 7 wpi | Quick jumpers, scarves and warm blankets | Spincycle Plump · Isager Alpaca 3 |
| Super chunkyCYC 6 US super bulky · roving | 8–12.75mmUS 11–17 | 7–11sts≈ 5–6 wpi | Cowls, fast blankets and statement knits | — |
| JumboCYC 7 US jumbo · roving | 12.75mm+US 17+ | 6sts or fewer≈ 1–4 wpi | Arm knitting, giant blankets and rugs | — |
• The weights we're asked for most CYC Craft Yarn Council standard number (0–7) wpi wraps per inch, for identifying unlabelled yarn
The "4" that trips everyone up
In the UK, 4 ply is one of the finest yarns on the shelf - fingering weight, for socks and shawls. In the US, a "4" on the label means worsted, a mid-weight for jumpers. Same numeral, opposite ends of the shop.
"Worsted" causes its own confusion, because it's both a weight and a way of spinning yarn - so a "worsted-spun 4 ply" is a fine yarn, not a mid-weight one. When a name and a number seem to disagree, ignore the name and read the gauge.
Reading the chart
The number is the one true name
Every yarn label carries a Craft Yarn Council number from 0 to 7 inside a little skein symbol. That number is the same the world over, while the words around it - DK, 8 ply, light worsted - change from country to country. When you're substituting yarn, match the number first. For the full method, see our guide to substituting yarn in a pattern.
The edges blur
These categories overlap more than a tidy table suggests. A heavy DK behaves like a light aran; our own Origin is a worsted that knits "like a heavy DK", and a lofty 4 ply like Opus happily passes for sport. The gauge you get on your needles decides where a yarn really sits - not the word on the band.
No label? Count the wraps
Wrap the yarn snugly around a ruler for one inch, with the strands side by side, and count them. Roughly 14 wraps is a 4 ply, 11 is DK, 9 is aran. It's a guide rather than gospel, so knit a tension square before you commit. And once you know the weight, our needle conversion chart will point you at the right needles.
Common questions
The ones we hear most across the counter on Walcot Street.
What is DK yarn?
DK stands for "double knitting". It's the Craft Yarn Council's weight 3 (Light), knits at about 21–24 stitches over 10 cm on 3.75–4.5 mm needles, and is called 8 ply in Australia and light worsted in the US. It's the most popular weight in British knitting - the comfortable middle ground for jumpers, cardigans and accessories.
What is the difference between aran and worsted?
They're the same Craft Yarn Council category - weight 4, Medium. "Aran" is the British name and "worsted" the American one, so a pattern calling for either wants roughly the same thickness. If there's a difference, aran tends to sit at the slightly heavier end. Confusingly, "worsted" is also a spinning method, which is a separate thing from the weight.
Is DK the same as worsted?
No. DK is weight 3 (Light) and worsted is weight 4 (Medium), so worsted is a step thicker. DK knits at about 21–24 stitches over 10 cm; worsted at 16–20. You can sometimes get away with substituting one for the other, but only after a tension square tells you the gauge works.
Is 4 ply the same as fingering?
Yes. UK "4 ply", US "fingering" and "sock" weight are all the Craft Yarn Council's weight 1 (Super Fine). The trap is the number: UK 4 ply is a fine yarn, whereas a "4" on an American label means worsted, which is much thicker. Read the weight name, not just the numeral.
What weight is sock yarn?
Almost always 4 ply / fingering (weight 1), knit on 2.25–2.75 mm needles for a dense, hard-wearing fabric. A few thicker patterns use sport-weight sock yarn, but "sock yarn" on its own means 4 ply.
How do I tell what weight my yarn is?
Check the ball band first - the Craft Yarn Council number (0–7) sits inside a small skein symbol, usually alongside a recommended needle size and gauge. If the label is long gone, wrap the yarn around a ruler for an inch and count the wraps: about 14 is a 4 ply, 11 is DK, 9 is aran. Then swatch to be sure.
Can I substitute one yarn weight for another?
Best results come from matching the same weight and a similar gauge to the one the pattern was written for. You can move a step across - a light aran for a DK, say - but the fabric, drape and yardage all shift, so a tension square is essential. Our yarn substitution guide walks through it properly.
What is the most common yarn weight?
In the UK it's DK, with aran close behind; in the US, worsted. All of them are mid-weights that strike the balance between knitting up at a sensible pace and being versatile enough for most garments - which is exactly why patterns favour them.
What weight yarn is best for a beginner?
DK or aran on 4–5 mm needles. They're thick enough to see your stitches clearly and knit up quickly enough to stay motivating, without being so bulky that the fabric feels unwieldy. A smooth, light-coloured wool makes it easier still.
Weight categories follow the Craft Yarn Council standard; names and gauges are guidelines, so always trust your pattern and your swatch. Not sure where a yarn sits? Bring it in - we'll wrap it and tell you.