What Are Those Numbers?

Have you ever found a cone of interesting yarn, looked inside the cone, read “8/2 cotton,” 10/3 linen or “10/3 wool” and wondered what those numbers mean?  It’s the yarn or thread count.  The yarn count or thread count is the number of yards of that specific yarn needed to make up one pound of a particular sized fiber (“YPP”).

The Handbook of Timesaving Tables for Weavers, Spinners and Dyers (Bettie G. Roth & Chris Schulz, 1993), sets out the yards per pound of various fibers as follows:

YPP	Fiber
840	Cotton, spun silk, rayon and acetate
300	Linen, hemp, jute, ramie & wool (cut system)
560	Worsted wool (spun system)
1,600	Wool (run system)

A.  Explanation

• #1 cotton = 840 yards
• #2 cotton (2x yardage and 1/2 diameter of #1) = 1,680 YPP
• #3 cotton (3x yardage and 1/3 of diameter of #1) = 2,520 YPP
• #8 cotton (8x yardage and 1/8 of diameter of #1) = 6,720 YPP
• #10 cotton (10x yardage and 1/10 of diameter of #1) = 8,400 YPP
• #12 cotton (12x yardage and 1/12 of diameter of #1) = 10,080 YPP
• #20 cotton (20x yardage and 1/20 of diameter of #1) = 16,800 YPP

B. Plies

• 8/3 = yarn size #8 in a 3 ply
• 10/2 = yarn size #10 in a 2 ply
• 20/5 = yarn size #20 in a 5 ply

C.  Formula for computing yardage

        (YPP)*(size of single thread) ÷ # of plies

             Example 1:  Computing YPP for Plied Cotton Yarn

• 8/3 = (840 x 8)/3 ply = 6,720/3 = 2,240 YPP
• 10/2 = (840 x 10)/2 ply = 8,400/2 = 4,200 YPP
• 20/2 = (840 x 20)/2 ply = 16,800 yards/2 = 8,400 YPP

             Example 2:  Computing YPP for Spun (Worsted) Wool

• 8/2 =(560 x 8)/2 ply = 2,240 YPP
• 8/3 = (560 x 8)/3 ply = 1,493.33 YPP
• 12/3 = (560 x 12)/3 ply =2,240 YPP
• 16/2 = (560 x 16)/2 ply = 4,480 YPP
• 20/5 = (560 x 20)/5 ply = 2,240 YPP

D.  What about cones of yarn without “those numbers?”

You may find yarn in a weight described as “wool, 1 pound cones, 1450 YPP” – no information about yarn size, diameter, plies, recommended gauge, et cetera.  So how do you classify this yarn?  Is it worsted? DK? Aran?  Though of course you will need to do a proper gauge before starting any project, it helps to classify the mystery yarn in cones so you can narrow down your selection.   The Craft Yarn Council provides a classification of standard yarn weights, but it is based on gauge, so that’s not easily helpful (unless you’re shopping at a store that allows you to gauge yarn before purchasing).

     1.  Chart

According to this handy chart courtesy of Spinderella’s Fiber Mill – the yarn in question probably would be somewhere in the DK to sport weight range.

(NOTE:  The best classification of weight is dependent on the type of wool, spinning and plies which might not bs supplied in the yarn description.  So buying yarn in this manner is best for experienced knitters and crocheters.  If you’re a newer knitter or crocheter, seek the advice of an experienced knitter/crocheter before buying.)

     2.  Another Way

Alternatively, you can pull out a calculator or pen & pencil and do a little math.  (I’m rounding to 2 decimal points.)

• Remember that 1 pound equals 16 ounces or 453.59 grams.
• Yarn skeins are generally sold in either gram (e.g. 25g, 50g, 100g) or ounce (e.g., 1.75 oz, 3.5 oz, etc.) weight.
• So convert the YPP – in this case 1450 – into yards per ounces or grams and then multiply to get the weight you want (e.g., 100 g or 3.5 oz):
•          For ounces:  1450/16 = 90.63y per oz = 317.19y per 3.5 oz skein
•           For grams:   1450/453.59y per gram = 3.20y per gram = 319.67 per 100g skein

E.  Conclusion

Armed (overloaded?!) with this information, you can go forth and buy cones of yarn with more confidence!