Embroidery Thread Sizes

Embroidery thread codes indicate thickness and ply.

If you are looking at embroidery as a new hobby, you may find there are a few more things to learn beyond stitching and design. Embroidery patterns can call for different sizes of embroidery thread. Knowing how to read embroidery thread codes can give you a good idea of what a project's texture will be and how to substitute in a pinch.

Thickness and Ply

Thread sizes are measured in numbers and letters. For instance, common thread sizes include: 150D/2, 120D/2 and 108D/2. The number before the slash indicates a thread's thickness, while the number following the slash indicates the ply of the thread. Two-ply means two strands of thread twisted together.

Formula

The "D" in the thread size stands for Denier. A Denier is a unit of measure --- grams of 9,000 meters' fiber. The formula for figuring Deniers is D=g/L*9,000 wherein "g" equals the weight of the fiber in grams and "L" equals the length of the fiber in meters.

What It All Means

If the number preceding the D is higher, the thread is thicker. If that number is lower, the thread is thinner. For instance, 120D is thicker than 108D. Also, the higher the number of plies, the higher the chances of the thread being thicker. The most common rayon thread is 120D/2, and the most common polyester thread is 108D/2.

References

• Quality Thread: Size of Embroidery Thread