The Ultimate Yarn Guide: Part 1 - Darn Good Yarn

The Ultimate Yarn Guide: Part 1

What is it that makes a Sport Weight Linen 2 Ply so perfect for a lightweight summer sweater? How can I tell how durable my yarn is? Why can I machine wash some wool, and not others? And what’s the deal with gauge? Is it actually important or not?

If yarn simply came down to what it was made of, there wouldn’t be a diverse and beautiful range of products people could create from it. There’s a great story behind every strand of yarn, one combining art, humanity, mathematics, and science.  

in this 2 part series, we will cover the main characteristics of what makes each type of yarn unique, from the specific fiber used to how it is twisted into strands. 


A fiber is a thread or filament that forms a textile. There are a diverse range of fibers; some come from natural sources, others from machines, and some are even a combination of both. It is important to understand the fiber behind the yarn, so that you can determine what would be best to make with the yarn, and how to treat it once the project is completed.

Animal Based

Animal based fibers are great insulators, that possess incredible breathability as well. Animal fibers consist of anything that is made from an animal, so the possibilities for projects varies greatly based on which type of animal fiber is being used.

The most popular animal fiber that is used is wool, which is great for creating warm sweaters, hats, mittens, and scarves. Most wool comes from sheep, but there are also other wool options, such as Yak, Alpaca Fleece, Cashmere, and even silk.

Due to the high sensitivity of these animal based fibers, it is always recommended that any project made with them are hand washed in cold water and laid flat to dry. (See “Care Instructions” below for more information.)

Plant Based (Also known as Cellulose Fibers)

Generally speaking, plant based fibers are softer and more breathable than animal fibers. Plant based yarn also offers a great alternative for those who follow a vegan lifestyle; they offer durability and comfort while also giving a peace of mind.

Two of the most common plant based yarns are cotton and linen, both of which are soft, yet durable, and great for creating shawls, scarves, and lightweight sweaters for warmer summer months. If you're looking for and incredibly durable plant based yarn, both hemp and nettle offer structure for creating everything from handbags to even cleaning supplies

A not so traditional plant based yarn is Banana Fiber Yarn, which was a ancient textile staple in all areas ranging from Okinawa to Africa.  Banana Fiber Yarn can also be a semi-synthetic fiber, meaning that most of the content come from natural sources, but some chemical processing is required. Other semi-synthetic yarns include Rayon, Viscose, Tencel and Lyocell. The process for creating these yarns is similar; use chemicals to process natural materials in order to create a new type of yarn. The different names represent the different trademark processes for each!

It is suggested that plant-based fibers be hand washed and dried, although they can be machine washed and dried. Putting these fibers in the washing machine or dryer can cause the garment to shrink; cotton can shrink up to 7% of the original size on its first round through the machines! After this initial shrinkage, the garment should remain that size regardless of the amount of subsequent washes. 


Synthetic Yarn has arguably become the most popular type of yarn, due to its low price point, accessibility, and ease of use. Some examples of synthetic yarn include acrylic, nylon, and metallic. Synthetic yarns are not only much simpler to knit and crochet with, but unlike animal and plant fibers, most synthetic yarn can be machine washed).


Yarn weight is arguably the most important factor when choosing a yarn. It determines what size needles or hooks you should use, gauge, and what type of project you can complete. Yarn weight is defined as the relationship between the length (ex: 100 yards) per unit (ex: ball), relative to the unit weight (ex: 50 g).

Here is a reference guide to help you determine which specific types of yarn, projects, needle size, and hook size fit each yarn weight.

Yarn Guide: Weight, Needle and Hook Size


WPI, or Wraps Per Inch, is a number that can be easily calculated with a pencil and a ruler. This is very useful to know, particularly when you want to determine the yarn thickness for scrap yarn, unlabeled yarn, or an old skein with a ripped off label.

Here are the 3 simple steps to determine WPI:

1. Collect your yarn (we used our Sari Silk Ribbon Cording), item to wrap the yarn around (we used a paintbrush)  and a measuring tape

How to Calculate Wraps per Inch

2. Wrap the mystery yarn around the paint brush (not too loose, not too tight), and be sure that there is not any space between the strands, or that the strands aren’t overlapping. Wrap until the section is about an inch wide.

How to Calculate Wraps per inch

3. Count the number of times you wrapped the mystery yarn around the pencil within that 1 inch section  

Based on the amount of wraps, our Sari Silk Ribbon Cording is a Bulky Yarn, with 8 Wraps per Inch.  Here are the wraps per inches for other yarn weights:

0 Lace Weight: 35 < wraps
1 Super Fine: 19-22 wraps
2 Fine: 15-18 wraps
3 Light: 12-14 wraps
4 Medium: 9-11 wraps
5 Bulky: 7-8 wraps
6 Super Bulky:  < 6 wraps


Yarn count determines the fineness or coarseness, or comfort and durability, in a yarn. In technical terms, yarn count is the “mass per unit length” of each fiber. While it is not as critical to note as yarn weight (you often won’t see yarn count when you buy skeins or hanks), it is useful to know when making yarn substitutions.

You can measure your own yarn count with a calculation, using either the direct or indirect method.

If you'd like to learn more in-depth about yarn count, click here.

Click here to view Part 2!