Tag Archives: WPI

Ask Nancy is Back!

Ask NancyWe haven’t heard from our resident expert, Nancy Reid in a bit. We’re happy to report that Ask Nancy is back!

Got weaving problems? Stumped by your spinning? Nancy will answer all of your burning questions with her expert advice. In this edition, we look at how we label our yarn weights; to ask your own question, email weavernancy@woolery.com 





I’m a knitter and a crocheter and I feel like I’m in foreign territory because I’ve never done wraps per inch, and I don’t understand 10/2 etc. Is there a chart that explains the equivalents to say lace yarn, sock yarn, sport weight yarn, etc?


In this case, I truly think it will be easier for you to learn the way we do it, rather than me translating; and I will explain why.


Going back to the Guild system in Middle-Ages Britain, each of the spinning guilds (flax, wool, silk) developed their own unique measuring system for the grist of their yarns, and those measures have persisted to this day.  So 10/2 cotton (for crochet, for example) does not equate in size to 10/2 wool (for fine knitting) or to 10/2 silk (a yarn usually used for weaving), or to 10/2 linen.  In all these yarns, the 10 is the gauge of the singles (for that fiber) and the /2 refers to the number of plies at that gauge.  These sizes run like wire sizes, in that the smaller the number, the bigger the wire; #10 is dryer wire and #22 is telephone wire, and #10 yarn is skinnier than #5 yarn.


So, each of these sizes is very precise; 8/2 cotton is 3360 yards per pound, period.  8/2 wool is 2240 yards/pound, period.  And because wool yarn is fluffier than cotton yarn, the diameters don’t match. either.  BUT: things are precise.  Worsted yarn, the way that the knitters talk about it, is a range of 900-1200 yards per pound; that’s a huge range, and lacks a lot of precision.  And since only the wool (and wool-ish, like wool blends and acrylic) yarns can be compared in the lace-fingering-sport-worsted-bulky system, the yards per pound system is the way that industry talks about them, and that system enables us to talk about all the yarns, made of all the fibers, in a common language.


Wraps per inch is a tool that some spinners, knitters, and weavers use to compare yarns; but it too lacks precision, and is just used for rough comparisons and is a starting place for sampling.
The standard knitting sizes are defined in the ranges of their yards per pound, and there is pretty good agreement there, though of course cotton, silk, and linen can’t be looked at with this yardstick.  Luckily, these fibers are not often knitted with, either!


Bulky is 600-800 yards per pound
Worsted is 900-1200 yds/#
Sport is 1200-1800 yds/#
Fingering (sock weight) is 1900-2400 yds/#
Lace is 2600+ yds/#


These equivalents should enable you to use the weights that we give on our wool (and alpaca) yarns to choose what you want to try to knit with.  For crochet purposes, when using cotton, #10 crochet cotton is 10/2; #5 crochet cotton is 5/2, #3 crochet cotton is 3/2.



Measuring Your Yarn

Yarn labels have a strange way of disappearing. When you go to your stash and find a naked skein or ball of yarn, how do you know what size it is?  One of our favorite go-to tools is a round wraps-per-inch gauge.  I’m sure you have seen some kind of wraps-per-inch (WPI) tool before.  They are usually flat with a little groove cut out of them or perhaps you learned to use a ruler.  What a great idea it was to make this handy tool round!  To use, secure one end of the yarn into the groove in the knob then twist until you have wrapped the yarn an inch on the gauge (two inches if you are measuring with irregular yarn such as slub, then take the average). Compare the wraps to the chart below to get an idea of the yarn’s size.

Type WPI
Lace 18 or more
Sock/fingering 16
Sport 14
Worsted 12
Bulky 10
Super-bulky 8 or less

What if you are a spinner and you want to measure your yarn WHILE you are spinning?  Here is another handy tool,  The Spinners Control Card. It allows you to lay a lenght of yarn on the gauge, to check your spinning as you work so that you don’t end up with a skein that is half fingering and half sport. Remember to take into consideration how many plies your yarn will ultimately have.  Spin a yarn half that thickness for two-ply, a third the thickness for three-ply, and so on.

While we are on the subject of measuring, you knitters will also want to keep a needle and swatch gauge handy.  Check out The Woolery’s gauge which is easy to use and offers a wide range of needle sizes measurements.

With the right tools you can take control of your stash in no time!

Chris, Nancy, and the entire Woolery team