Yarn twist has a direction as well as an amount. Getting it right avoids subtle but real fabric problems.
S and Z, defined
Look at a vertical yarn: if the spirals run like the middle of the letter Z (bottom-left to top-right), it is Z-twist; like the letter S, it is S-twist. Ring-spun single yarn is usually Z-twist.
Why direction matters
- Two-fold yarn is usually plied in the opposite direction to the singles for a balanced, stable yarn.
- Twill fabrics can look sharper or flatter depending on how twist direction relates to the weave direction.
- Crepe and voile use alternating S and Z twist yarns for their characteristic surface.
What to specify
For most fabric you can leave it to standard practice, but for crepe, fine wovens or matched-twill effects, specify the twist direction. Set the twist amount with our twist calculator and read more on twist multiplier.
Need a specific twist and direction? We match it to your fabric.
More in our yarn guides and glossary.