Have you ever finished a single crochet project and thought, “Hmm… something looks a little off”? Maybe your seams are slanting, your amigurumi looks lopsided, or your fabric feels too holey (or too tight).
The secret might not be your tension at all – it could be whether you’re doing Yarn Over (YO) or Yarn Under (YU) single crochet! These two tiny technique differences create dramatically different results, and most crocheters don’t even realize there are two official ways to make a single crochet stitch. Let’s break it down side by side so you can finally choose your side in the great Yarn Over vs Yarn Under debate...or happily switch between them like a pro.
This is Part 2 of our deep dive into crochet basics (check out Part 1: Double Crochet and Part 3: Half Double Crochet for more!).
How to make Single Crochet (Sc) - Two Ways
 |
Yarn Over (YO) Sc – Insert the hook into the stitch, Yarn Over and pull up a loop, Yarn Over and pull through 2 loops on the hook. This stich is known as a Traditional Sc.
|
 |
Yarn Under (YU) Sc – Insert the hook into the stitch, Yarn Under and pull up a loop, Yarn Over and pull through 2 loops on the hook. This stich can also be referred as “Hook Over”. |
How the Stitches Look Up Close
YO single crochet:
- Two almost-parallel legs → looks like a neat little “||”
- Straight stitch / offset placement from row to row
- Slightly taller and airier fabric
YU single crochet:
- Crossed legs → looks like a tiny “X”
- Slightly slanted textured stitch / counterbalanced placement from row to row
- Shorter, tighter, and denser fabric; perfect for amigurumi that need zero stuffing peek-through
The Surprising Effect on Projects Worked in the Round
Here’s where things get wild. When you crochet in the round and join with a slip stitch:
YO single crochet → every round shifts a tiny bit to the right (right-handers) or left (left-handers). Result: a visible spiral or slanted seam over time.
|
RIGHT Handed Crochet |
LEFT Handed Crochet |
|
|
|
YU single crochet → the slight slant of each individual stitch cancels out the round-by-round shift. Result: perfectly straight vertical seams – magic!
Achieve Perfect Symmetry in the Round (YO or YU – Both Work!)
When you crochet ovals, soles or any other shapes that start from a foundation chain and are worked in spiral rounds, traditional Yarn Over (YO) single crochet slowly drifts to one side, making the piece look slanted. Don't worry, you have two simple ways to keep everything perfectly straight and symmetrical:
• Stick with YO? Work in joined, turned rounds (slip-stitch to join, turn your work, ch-1 to begin the next round). Turning flips the slant back and forth so it cancels itself out.
• Love spirals? Switch to Yarn Under (YU) single crochet. The slight twist in each YU stitch naturally counter-balances the spiral drift, giving you dead-straight seams (no extra steps).
YO single crochet (Spirals Rounds) → the shape looks slightly slanted.
|
RIGHT Handed Crochet |
LEFT Handed Crochet |
|
|
|
YO Single Crochet (Joined & Turned Rounds) → the shape looks straight.
YU Single Crochet (Spiral Rounds) → the shape is naturally straight and symmetrical.
When to Choose Which One (Cheat Sheet)
Use Traditional Yarn Over (YO) single crochet when:
• You’re crocheting flat rows (back and forth) – the stitches line up beautifully straight
• Your wrists or hands get sore easily (YO is gentler on the joints)
• You want a softer, drapier fabric (blankets, scarves, garments)
• You learned the “classic” way and love tradition
Use Modern Yarn Under (YU) single crochet when:
• You want that adorable cross-stitch “X” look everyone loves
• You’re making amigurumi, toys, or anything stuffed (no holes!)
• You need perfect symmetry in the round (soles, ovals with symmetrical details, rectangles, and other geometrical motifs)
• You want straight seams
PRO TIP: You can totally be bilingual! Many designers (including me) use YO for wearables and YU for toys.
Gauge Got You Down?
If you keep matching stitch gauge but your rows are always too short or too tall, try switching techniques before you go down a hook size. Yarn Under single crochet is noticeably shorter than Yarn Over, so it can fix row height problems instantly.
Final Notes
The Golden Rule - Whatever you do, stay consistent throughout a project! Mixing the two in the same piece creates an obvious texture change that’s hard to hide.
My Personal Take - I’m 100% Team Yarn Under for almost everything I design now. I love the tight fabric, the cute little X’s, and those perfectly straight seams on hats and amigurumi. But the moment my wrists start complaining on a big blanket project? Hello again, old friend Yarn Over.
There’s no “wrong” way – only the way that makes you and your project happiest.
Now that you know the secret… which team are you?
Drop a comment and tell me – are you a die-hard Yarn Over fan, newly converted to Yarn Under, or happily switching like a crochet ninja?
Happy stitching!
