Yarn measurement can be a bit of a grey area, with mystery numbers flying around and unidentifiable units. Let’s clear everything up here!

There are many yarn count measurement systems but three common ones are:

English cotton count (ne) is often used for cotton and cellulose yarns like SeaCell, Tencel, and viscoses.
Metric (nm) is more often used for silks and silk blends though it can and should (!!) be used for everything.
Linen is usually measured in NeL/lea.

When you buy yarns for weaving, they are very likely to give a yarn count in one of these (or other similar) measurement systems. That yarn count figure is made up of three pieces of information.

The yarn count of each ply tells you what the length per weight would be if the yarn were only a single ply.

The number of plies tells you how many individual spun strands make up the yarn. This is commonly a 1 or 2, for either an unplied or a two ply yarn but can be more.

The unit of measure says what measurement system the yarn count is given in.

Now that we know how to read that number, how do we translate it?

 

Final Yarn Count

No matter which of these above yarn count units we’re using, the calculation is essentially the same. In order to do the calculation we have to first take the yarn count and put it into a single number, the final yarn count.

Luckily, this is very easy to do! Just divide. 8/2=4. As an example, the popular 8/2ne cotton has a final yarn count of 4ne.

What about 20/2nm silk? 20/2=10. That gives a final yarn count of 10nm.

One tricky exception is when a yarn has been uptwisted. For example: 3x16/2ne. That means that three strands of two ply 16ne have been plied together. That means that this really is 16/6ne, because there are six plies total. The reason it’s written as 3x16/2ne is to show that it’s been uptwisted. In this case the yarn will have a final yarn count of 16/6=2.67ne.

Translating Final Yarn Count to Length

The final yarn count tells us the total length per weight of the yarn. Once we have that number, we can use the key below to multiply and get the total number.

Measurement system Units Definition
English cotton count ne 840 yards per pound
Metric nm 1000m/kg
Linen count nel / lea 300 yards per pound

 

Examples

Yarn 8/2ne cotton
Final yarn count 8/2=4ne
Conversion 1ne = 840 yards per pound
Calculation 4ne*840 yards per pound
Total =3360 yards per pound

 

Yarn 20/2nm silk
Final yarn count 20/2=10nm
Conversion 1nm = 1000m/kg
Calculation 10nm*1000m/kg
Total =10000m/kg

 

Yarn 16/2nel linen
Final yarn count 16/2=8nel
Conversion 1nel = 300 yards per pound
Calculation 8nel * 300yards per pound
Total =2400 yards per pound

 

Yarn 3x30/2ne viscose
Final yarn count 3x30/2ne = 30/6ne = 5ne
Conversion 1ne = 840 yards per pound
Calculation 5ne * 840 yards per pound
Total =4200 yards per pound

Converting between metric and imperial

Now we know how quick and easy it is to get the length per weight, we just need to quickly convert between metric and imperial. For some people that’s a moment’s calculations. For other’s it’s a pain, so here’s the quickest, simplest cheat:

To convert from: Multiply by:
Yards per pound to m/kg 2.02
m/kg to yards per pound 0.495

 

That’s it!

Now you know what the conversions mean, how to use them, how to translate between them, and why it’s important to always use the units in yarn counts!

Good luck and I hope this was helpful!