If you have ever seen yarn described as 4 ply, 6 ply, or 8 ply and felt confused, you are not alone. Many beginners think ply and yarn thickness (also called yarn weight) mean the same thing, but they are actually different things.
This simple guide explains the difference, so you can choose the right yarn with confidence when shopping Hobby Store yarns on Magic Needles.
The Short Answer
- Yarn weight (thickness) = How thick the yarn strand is (DK, Aran, Bulky, etc.)
- Yarn ply = How many smaller strands are twisted together to make the yarn
Two yarns can have:
- The same ply but different thickness
- The same thickness but different ply
So, ply and thickness are not the same thing.
What Does “Ply” Actually Mean?
Ply means the number of individual strands twisted together to make one yarn.
For example:
- A 4 ply yarn is made by twisting 4 thin strands together
- A 6 ply yarn is made by twisting 6 thin strands together
More plies usually mean:
- The yarn can be stronger
- The yarn can feel rounder and smoother
- Often better stitch definition
But more plies does not automatically mean the yarn is thicker.
Then What Is Yarn Thickness (Weight)?
Yarn weight (also called thickness) is about how thick the final yarn strand is. This is what patterns care about the most.
You will see names like:
- Fine, Sport, DK
- Aran, Worsted
- Bulky, Super Bulky
If you want to shop by thickness, you can use:
For a full explanation, read:
👉 Yarn Weights Explained: How to Choose the Right Yarn and Needle or Hook Size
Why Ply and Thickness Get Confused
In some countries, terms like “4 ply” or “8 ply” are used to roughly suggest thickness. But modern yarns do not follow a strict rule anymore.
For example:
- You can find 4 ply yarns that fall into Fine or DK weight ranges
- You can find multi-ply yarns that still fall into Aran or even Bulky weight ranges
So today, the safest and best way to choose yarn is:
Follow the yarn weight (DK, Aran, Bulky, etc.), not just the ply number.
Real Example from Hobby Store Yarns
You might see yarns like:
- Hobby Store Cotton – Aran
- Hobby Store Merino Wool – Aran
They both fall in the Aran weight range, which means they are in the same thickness category, but not necessarily exactly the same thickness. Their ply structure and fiber can be different, which changes:
- How the yarn feels
- How smooth or round the stitches look
- How strong or soft the fabric is
Which One Should You Follow: Ply or Weight?
Always follow the yarn weight in the pattern.
Patterns are written for:
- A specific thickness of yarn
- A specific hook or needle size
If you match the yarn weight, your project size and look will be much closer to what the pattern expects.
Ply is more about:
- Yarn construction
- Strength and texture
- How the stitches look and feel
Does Ply Matter at All?
Yes, but in a different way.
Ply can affect:
- Stitch definition (multi-ply yarns often show stitches more clearly)
- Durability (more plies can mean stronger yarn)
- Feel (some plied yarns feel smoother and rounder)
Think of it like this:
- Weight decides if the yarn fits the pattern
- Ply helps decide how the fabric will look and feel
A Simple Shopping Rule (Beginner-Friendly)
- First, match the yarn weight (DK, Aran, Bulky, etc.)
- Then, choose the fiber you like (cotton, acrylic, wool, etc.)
- Finally, look at the ply and texture for stitch definition and feel
To browse by thickness the easy way:
How This Connects to Our Other Guides
- Yarn Weights Explained helps you pick the right thickness
- How Much Yarn Do You Need? helps you buy the right quantity
- The Ultimate Beginner’s Guide to Crochet and Knitting helps you get started
Final Thoughts
Ply and thickness sound similar, but they answer two different questions:
- Thickness (weight): Will this yarn work for my pattern?
- Ply: How will this yarn look and feel once I make the fabric?
Once you keep that difference clear, choosing yarn becomes much simpler and far less confusing.
