The one thing all yarn arts have in common is the yarn itself. And what a variety of yarn there is! All the different weights or thicknesses of yarn can be overwhelming. It can be confusing as to what can be made with certain weight yarns if you have never used it before. Questions always abound when it comes to yarn weights. What is yarn weight? Which weight yarn do I use? How many strands do I use to equal a heavier weight? Is 4ply and worsted the same? What in the world is WPI???
Let’s start at the beginning.
What is yarn weight?
Well first of all, yarn weight has nothing to do with the net weight of the hank, skein, or ball of yarn. It has nothing to do with the yardage either. When yarn weight is discussed, it is referring to the thickness or diameter of the yarn.
Here in the USA, yarn is labeled by a number system to differentiate between the different thicknesses of yarn although there are other terms or common names associated with those weights as well. The yarn weight can be found on the label of the yarn. It is a symbol of a yarn skein or ball with a number on the label like this one.
Not all yarns will have this since it depends on where the company is actually located.
Yarn weight is actually determined by the wraps per inch or WPI instead of the actual diameter of the yarn.
What is WPI?
WPI stands for Wraps Per Inch. You can easily determine the weight of “mystery” yarn you have in your stash that has lost its label, handspun yarn you either spun yourself or bought, or mill ends by counting how many wraps are in an inch. There are different ways you can do this. You can buy a WPI tool or just use a pencil and use a ruler to measure. Or you can just use the ruler to wrap the yarn and measure at the same time.
The WPI tool is a very neat tool that has the inches marked on the round stem with a notch at the end to hold the yarn so you can wrap the stem. It usually comes with a card that has the instructions on one side and the yarn weights with WPI on the other. Very handy but not necessary.
You can use a pencil or pen to do the same thing. Then measure and count the wraps in an inch by using a ruler. In the picture below, I wrapped more than an inch and started counting from the second wrap until I reached the 1″ mark. There are 9 wraps in an inch.
You can also just use a ruler to wrap the yarn around. The problem with this method is the possibility of twisting the yarn while wrapping which will stretch it so care is needed when using just a ruler. I would recommend starting at the 1″ mark and wrapping to the 2″ mark on the ruler instead of starting at the end of the ruler. If you start at the end, it is harder to keep the end wraps from falling off the ruler. As you can see below, it is harder to read the marks on the ruler when the yarn is wrapped on it instead of a pencil. There are 6 wraps in an inch.
When you wrap the pencil or ruler, you need to make sure the yarn is not pulled tight or pushed together. It needs to be relaxed. You just roll the pencil or turn the ruler to wind the yarn on whichever you are using. Rolling instead of just wrapping will keep the yarn from being twisted which will cause the yarn to pull tighter and be thinner than it actually is. Do not pull on the yarn at all. Tension will stretch the yarn and cause it to be thinner than it is. Let each wrap rest next to the previous wrap without being pushed together. If the yarn has a halo, like mohair, you will need to give the yarn more room between wraps for the “fuzzy” hairs to expand. This is why mohair yarn always has a heavier weight than it would appear to be. It is not measured by just the diameter of the yarn but also how far the halo extends as well.
Count the number of times the yarn is wrapped around for 1 inch. Some instructions will say to wrap 2 inches, count the wraps, and divide by 2. This is not necessary unless you are measuring yarn with “character” like a thick and thin yarn. Then you would need to wrap 3 inches and divide by 3 to get a good count.
The number counted in 1 inch is the WPI. Then compare that number to the chart below to find your yarn weight.
What are the different weights of yarn available?
Since the new weight classification has been added, there are now 8 different categories in the USA yarn weight system. Some of the common names overlap depending on location and how it was taught. Please note that some people will include aran as a bulky weight yarn. While it is thicker than worsted, aran is still included in the medium weight category due to it’s WPI. Also, Caron Simply Soft and Red Heart Boutique Unforgettable are considered medium weight as well even though both are thinner which can make the entire medium weight category confusing for some people.
Weight # Common Name WPI
0 – lace Cobweb/Thread/Lace/Sock 23 and greater
1 – super fine Lace/Sock/Fingering 19 – 22
2 – fine Baby/Sport/Lace 15 – 18
3 - light Sport/DK/Baby 12 – 14
4 - medium. Worsted/Aran 9 – 11
5 – bulky Bulky 7 – 8
6 - super bulky. Super Bulky 5 – 6
7 – jumbo Jumbo 4 and less
Why are the weights different other places?
Not all countries use the same names for yarn weights. It can sometimes get confusing since the internet makes the world smaller. There are pattern writers all over the world that use the yarn classifications of their country. I have bought yarn from the UK on several occasions. You will need to know what the names of the yarn weights are so you can buy the correct yarn. For example, 4 ply is NOT 4 weight yarn. It is a lot thinner. Yarn weight is not determined by the number of plies. And that leads us to our next question…
What are the yarn weight equivalents between the USA and UK?
USA Weight UK Term
0 - lace 1 – 3 ply
1 - super fine 4 ply
2 - fine 5 ply
3 -light DK/8 ply
4 - medium Aran/10 ply
5 - bulky Chunky/12 ply
6 - super bulky Super Chunky
7 – jumbo unknown
What weight yarn do I use with certain looms?
A lot of times, the weight of yarn you use with certain looms will depend on the stitch pattern or the way you want the finished project to look. Each person has their own idea of what is too tight or too loose. Tension is a factor as well since each person’s tension is different. It is sometimes hard to say what weight yarn is best for each gauge loom, but it can be helpful to have a starting place until you learn which is best for you. If you are unsure what gauge loom you have, you can learn more about gauge here.
Extra fine gauge – lace/super fine
Fine gauge – super fine/fine/light
Small gauge – light/medium
Regular gauge – light/medium/bulky
Large gauge – bulky/super bulky/jumbo
Extra large gauge - super bulky/jumbo
How many strands will equal a heavier weight?
Needing a heavier weight yarn than you have in your stash? All you need to do is use more than 1 strand. But how many strands will equal what you need?
If you use 2 strands of yarn, it will be equivalent to the next heavier weight. So if you have a 4 weight yarn and need a 5 weight yarn, use 2 strands together as 1.
Here is an easy way to see what you need:
2 strands of 1 weight = 1 strand of 2 weight
2 strands of 2 weight = 1 strand of 3 weight
2 strands of 3 weight = 1 strand of 4 weight
2 strands of 4 weight = 1 strand of 5 weight
2 strands of 5 weight = 1 strand of 6 weight
2 strands of 6 weight = 1 strand of 7 weight
But what if I only have 4 weight and need a 6 weight? Since 2 strands of 4 weight equals 1 strand of 5 weight and 2 strands of 5 weight equals 1 strand of 6 weight, then 4 strands of 4 weight will equal 1 strand of 6. 3 strands of 4 weight will be a heavier 5 or a lighter 6 weight yarn.
Hopefully this will help in trying to decide which yarn weights are best for which looms and for finding out what weight that mystery yarn is that keeps getting pushed aside.
Keep asking questions! Questions lead to answers, and answers lead to knowledge.
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Reminiscent of days gone by, the cloche is knit in two parts, the band and the body of the hat, all in stockinette stitch. The slanted band around the brim gives the cloche its beauty. Decorate it with a one-of-a-kind button and you have a unique cloche.
Knitting Loom: 40 peg large gauge knitting loom. Sample was knit using the Adjustable Hat Loom, set to large gauge and 40 pegs.
Yarn: Approx 110 yards of super bulky weight yarn. Sample was knit using Knit Picks Biggo in Shappire Heather (1 skein).
Notions: Knitting tool, tapestry needle.
Other: Decorative button
Gauge: 11.5 sts x 20 rows = 4 rows in stockinette
K=knit stitch. Recommend the knit stitch or the u-stitch; do not recommend the flat stitch or the ewrap.
P= purl stitch
CO=cast on (Sample uses the ewrap cast on to provide an elastic fit).
GBO=gather bind off
K2tog= knit two stitches together. A right slanting decrease.
P2tog=purl two stitches together.
Brim band is worked separately from the body. Band is mattress stitched to the body after both parts have been knitted.
Set up the Adjustable Hat Loom to 40 pegs, at large gauge: 2 rounded parts, 4 connectors (3 peg), 2 peg rails (9 peg).
Cast on 40 sts, join to work in the round.
Round 1-32: k to the end of round.
Next round: *k2tog; rep from * to the end of rnd.
Move the stitches from the odd numbered pegs to the even numbered pegs. Knit the round, skipping the pegs with no stitches and treating the pegs with two loops as one loop.
Bind off with the gather removal method. As you bind off, gently tug on each of the stitches, starting with the first peg, to remove any of the extra slack in the yarn.
Weave all ends in. Wet block to set the stitches.
Cast on 6 sts, prepare to work a flat panel.
Row 1-8: Sl 1, k1, p2, k2.
Row 9: Sl 1, k1, m1, p2, k2. (7 sts)
Row 10-18: Sl 1, k1, p3, k2.
Row 19: Sl 1, k1, m1, p3, k2. (8 sts)
Row 20-28: Sl 1, k1, p4, k2.
Row 29: Sl1, k1, m1, p4, k2. (9 sts)
Row 30-38: Sl, k1, p5, k2.
Row 39: Sl 1, k1, m1, p5, k2. (10 sts)
Row 40-48: Sl1, k1, p6, k2
Row 49: Sl 1, k1, p2tog, p4, k2. (9 sts)
Row 50-58: Sl 1, k1, p5, k2
Row 59: Sl 1, k1, p2tog, p3, k2. (8 sts)
Row 60-68: Sl 1, k1, p4, k2.
Row 69: Sl 1, k1, p2tog, p2, k2. (7 sts)
Row 70-78: Sl 1, k1, p3, k2.
Row 79: Sl 1, k1, p2tog, p1, k2. (6 sts)
Row 80-88: Sl 1, k1, p2, k2.
Bind off with basic bind off method. Leave a 20 inch yarn tail for seaming.
Wet block BODY and BAND before assembly.
Using yarn tail from the band, mattress stitch seam the band to the cast on edge of the hat. Be sure to seam loosely so the seam is loose. The band is approx an inch longer than the circumference of the hat, secure the band end with the button. Weave ends in. If necessary, wet block again.