What decreasing means and why you need it
Decreasing is removing stitches from your needle to shape your knitting. You use it to taper sleeves, form necklines, create shaping in the body of a garment, and build the sloped sides of hats and socks. Without decreases, every piece you knit would be a rectangle.
The most common decreases remove one stitch per row or round. Some remove two or more at once for sharper shaping. The method you choose affects how the decrease looks — whether it leans left, right, or sits neutral — and how visible it is in the finished fabric.
Most patterns will tell you which decrease to use and where. If yours does not, a knit two together (K2tog) works for most situations. The key is consistency: use the same decrease in the same spot on every row so your shaping looks intentional and even.
Key Takeaways
- Knit two together (K2tog) is the most common decrease and works for most patterns; you insert your needle through two stitches at once and knit them as one.
- Slip, slip, knit (SSK) is the left-leaning version of K2tog and pairs with it to create balanced shaping on both sides of a piece.
- Purl two together (P2tog) is the purl-side equivalent of K2tog and is used when you are working on the wrong side or in ribbing.
- Double decreases like slip 2 stitches together, knit 1, pass slipped stitches over (SK2P) remove two stitches at once and create a centered line of shaping.
- Placing decreases one stitch in from the edge creates a chain-like selvage that looks neater than decreasing at the very edge.
Knit two together (K2tog) — the standard right-leaning decrease
K2tog is the decrease you will use most often. Insert your right needle through two stitches on your left needle from left to right, as if you were going to knit them normally. Knit them together as a single stitch. You have removed one stitch from your needle.
K2tog leans to the right. This matters when you are shaping both sides of a piece — a sleeve cap, a V-neck, or the sides of a cardigan. On the right side of the piece, use K2tog. On the left side, use SSK (described below) so the decreases mirror each other and the shaping looks balanced.
Work K2tog one stitch in from the edge rather than at the very edge itself. This creates a neater selvage and makes seaming easier later. For example, on a sleeve cap, knit one stitch, then K2tog, then knit to the end.
Slip, slip, knit (SSK) — the left-leaning decrease
SSK creates a left-leaning decrease that pairs with K2tog. Slip one stitch knitwise (as if to knit), slip another stitch knitwise, then insert your left needle through both slipped stitches from left to right and knit them together. The result looks like a mirror image of K2tog.
Use SSK on the left side of your piece when K2tog is on the right side. This creates symmetrical shaping. If your pattern says "decrease 1 stitch each side," it usually means K2tog on one side and SSK on the other, though some patterns will spell this out.
SSK takes one extra step compared to K2tog, so it is slightly slower. Some knitters find it awkward at first. If you struggle with it, slip 1, knit 1, pass slipped stitch over (SKPO) works the same way visually and may feel easier — slip one stitch knitwise, knit one, then pass the slipped stitch over the knit stitch.
Purl two together (P2tog) and other purl-side decreases
When you are working on the wrong side of your piece or working in ribbing, you decrease on the purl side using purl two together (P2tog). Insert your right needle through two stitches from left to right and purl them together as one stitch. P2tog leans to the left on the knit side of the fabric.
If you need a right-leaning decrease on the purl side, use slip 1, purl 1, pass slipped stitch over (SPPO). Slip one stitch purlwise, purl one, then pass the slipped stitch over. This mirrors SSK on the knit side.
Most patterns worked flat (back and forth on straight needles) will specify which decrease to use on the purl rows. If yours does not, P2tog is the safe choice for most situations.
Double decreases for centered shaping
Double decreases remove two stitches at once and create a visible centered line. The most common is slip 2 stitches together, knit 1, pass slipped stitches over (SK2P). Slip two stitches together knitwise as if they were one, knit the next stitch, then pass both slipped stitches over the knit stitch. You have removed two stitches and created a line that leans slightly right.
Use SK2P at the center of a V-neck, at the peak of a hat crown, or anywhere you want a sharp, visible decrease line. The center stitch (the one you knit) sits on top, creating a decorative effect.
Another option is centered double decrease (CDD), which is slip 2 stitches together knitwise, knit 1, pass slipped stitches over — the same as SK2P. Some patterns call it by different names, but the method is identical. A few patterns use slip 1, knit 2 together, pass slipped stitch over (S1K2togPSSO), which is the same result worked in a different order.
Where to place decreases so they look intentional
Decreases at the very edge of your piece can look sloppy and are hard to seam. Instead, work one or two stitches in from the edge, then place your decrease. For a sleeve cap, knit one stitch, work your decrease, knit to the last three stitches, work your decrease, knit one stitch. This creates a chain-like selvage on both sides that looks finished.
On pieces worked in the round (like hats and socks), place decreases in the same column on every round. This creates vertical lines of shaping that look intentional. Mark your decrease rounds with a stitch marker if the pattern does not specify exactly where they go.
Spacing matters too. If your pattern says "decrease every row," work the decrease on every single row. If it says "decrease every other row," work the decrease, knit one row without decreasing, then decrease again. Uneven spacing makes shaping look accidental.
Common mistakes and how to avoid them
The most common mistake is mixing K2tog and SSK on the same side of a piece. This creates unbalanced shaping where one side leans right and the other leans right too, instead of mirroring. Check your pattern and use the correct decrease on each side.
Another mistake is decreasing too close to the edge. This makes seaming harder and the selvage looks rough. Always work at least one stitch in from the edge before you decrease.
Tension matters. If your decreases are much tighter or looser than the rest of your knitting, they will stand out. Work your decreases at the same tension as your regular stitches. If you tend to work decreases tightly, consciously relax your tension on those rows.
Frequently Asked Questions
What is the difference between K2tog and SSK?
K2tog leans to the right; SSK leans to the left. They remove the same number of stitches but create mirror-image decreases. Use K2tog on the right side of a piece and SSK on the left side so your shaping looks balanced.
Can I use K2tog on both sides instead of mixing it with SSK?
You can, but the shaping will look unbalanced because both decreases lean the same direction. Most patterns pair K2tog and SSK specifically to create symmetrical shaping. If your pattern does not specify, use them as a pair.
What does it mean when a pattern says "decrease 1 stitch each side"?
It means remove one stitch from each side of the piece on the same row or round. Usually this means K2tog on one side and SSK on the other. Some patterns will say "K2tog on the right side, SSK on the left side" to be explicit.
How do I know which decrease to use if my pattern does not say?
K2tog works for most situations. If you are shaping both sides of a piece (like a sleeve), use K2tog on the right and SSK on the left. If you need a centered decrease line, use SK2P. When in doubt, K2tog is the safe choice.
Why do my decreases look loose compared to the rest of my knitting?
You may be working your decreases with looser tension than your regular stitches. Consciously tighten your tension slightly on decrease rows, or work the stitch after your decrease a little tighter to close the gap. Uneven tension usually evens out after blocking.