Knitting Increases and Decreases: A Complete Guide

# Increases and Decreases in Knitting: A Complete Technique Guide

If you've ever stalled out on a raglan sweater or a lace shawl because the pattern suddenly demanded "ssk" or "M1L," you're in good company. Increases and decreases are the tools that turn a flat rectangle of fabric into a sock heel, a sleeve cap, a fitted yoke, or a lace leaf. Once you understand what each stitch actually does to your fabric—and, just as importantly, which way it leans—you'll stop treating shaping instructions as a mystery to survive and start using them as a design tool.

This guide walks through the most common increases and decreases in knitting, explains the mechanics behind each one, and shows you how to choose the right stitch for the shaping situation in front of you.

Why "Which Stitch" Matters More Than You Think

Every increase adds a stitch to your row; every decrease removes one. But not all increases or decreases look—or behave—the same. Some are nearly invisible, blending into the surrounding stockinette. Others create a visible line, ridge, or hole that becomes a design feature in its own right (think lace eyelets). And critically, most decreases lean either left or right, the way a diagonal stroke in a letter "V" leans one way on the left side and the other way on the right.

That lean is the detail that separates a professional-looking garment from one that looks slightly "off," even if nobody watching can say exactly why. On a raglan sweater, a V-neck cardigan, or a set-in sleeve cap, you're almost always shaping in mirrored pairs—removing or adding stitches near the same two points on opposite sides of the work. If you use a right-leaning decrease on both sides instead of pairing a left-leaning one with a right-leaning one, the fabric will still be the correct width, but the diagonal lines of your shaping will point the same direction instead of mirroring each other, and the piece will read as asymmetrical even though the stitch counts match perfectly.

Increases: Adding Stitches Without a Trace (Or With One, On Purpose)

Yarn Over (yo)

A yarn over is the simplest increase in knitting: you wrap the working yarn over the right-hand needle before working the next stitch, creating an extra loop with no corresponding stitch beneath it. Worked on its own, this leaves a visible hole—which is exactly why it's the backbone of lace and eyelet patterns. A yarn over is never invisible, and that's the point: use it whenever the pattern wants decorative openwork, not when you need shaping that disappears into stockinette.

Knit Front and Back (kfb)

Also written as "kf&b" or "inc1," this increase works into the same stitch twice: knit it normally without sliding it off the left needle, then knit into the back loop of that same stitch before finally dropping it. One stitch becomes two. Kfb is quick and beginner-friendly, but it leaves a small horizontal bump—a tiny purl-like bar—sitting just above the increase. That bump makes kfb easy to identify visually, which is handy for garter-stitch or textured patterns where it can blend in, but a poor choice for smooth stockinette shaping where you want the increase to disappear.

Make One (M1L and M1R)

The "make one" increase family is the go-to choice when you want shaping that's nearly invisible in stockinette. You work it by lifting the horizontal strand of yarn that runs between the stitch you just worked and the next stitch on the needle, placing it onto the left needle, and knitting into it—effectively knitting into thin air between two existing stitches rather than doubling up an existing one.

The direction you lift that strand from, and which leg you knit into, determines the lean:

• M1L (Make 1 Left): Insert the left needle from front to back under the strand, then knit into the back leg. The resulting stitch leans left.
• M1R (Make 1 Right): Insert the left needle from back to front under the strand, then knit into the front leg. The resulting stitch leans right.

A handy memory trick: "right" and "front" both work, in a sense, with the front leg, while "left" pairs with the back leg. Because M1L and M1R are mirror images of each other, they're the standard pairing for symmetrical shaping—for example, working an M1L a couple of stitches in from one raglan seam and an M1R the same distance in from the other, so the fabric fans outward evenly on both sides.

Lifted Increases (LLI and RLI)

A lifted increase creates a new stitch by knitting into the "leg" of a stitch one row below the working needle, rather than into the running strand between stitches. Because it uses actual stitch fabric rather than the yarn tension between stitches, a lifted increase tends to be even less visible than an M1, which makes it popular in fine-gauge or highly visible pieces like the sleeve caps of a fitted sweater. Like make-one increases, lifted increases come in left- and right-leaning versions (often abbreviated LLI and RLI) and are typically paired the same way, one on each side of a shaping line.

Decreases: Removing Stitches With Direction and Purpose

Knit 2 Together (k2tog)

The most common decrease in knitting, k2tog simply means inserting the right needle through two stitches at once, as if they were a single stitch, and knitting them together. The result leans to the right: the stitch that was on the left ends up sitting on top of, and slanting over, the stitch that was on the right. Because it's fast and produces a clean, close-to-invisible line in stockinette, k2tog is often the default decrease worked at the end of a right-side shaping row, on the right edge of a shaped piece.

Slip, Slip, Knit (ssk)

SSK is the standard mirror image of k2tog. You slip two stitches individually, knitwise, from the left needle to the right, then insert the left needle through the fronts of both slipped stitches and knit them together. The result leans left—the stitch that was on the right ends up sitting on top of and slanting over the one on the left. Some knitters find a plain ssk sits slightly less flat than k2tog; slipping the first stitch knitwise and the second purlwise before knitting them together (sometimes called a "slip 1, slip 1 purlwise" variant) can tidy up the finished look, though a plain ssk is perfectly serviceable for most projects.

Because k2tog leans right and ssk leans left, this pair is the classic combination for symmetrical shaping: work an ssk near the start of a row and a k2tog near the end (or vice versa, depending on your pattern), and the two decrease lines will angle toward or away from each other in a mirrored, deliberate-looking way—exactly what you want flanking a V-neck or running up both sides of a raglan yoke.

Double Decreases: sk2p and k3tog

Sometimes a pattern needs to remove two stitches at once rather than one, most often at the center of a V-neck or the point of a lace motif.

• K3tog knits three stitches together in one motion, much like an oversized k2tog. It slants to the right, the same direction as k2tog, and is quick to work but not perfectly centered.
• SK2P (slip 1 knitwise, k2tog, then pass the slipped stitch over) removes two stitches while keeping the decrease closer to vertical, since the slipped stitch travels up and over the k2tog rather than simply leaning in one direction. It's frequently chosen for centered double decreases where you want the line of decreases to sit dead center along a garment's spine, such as down the middle front of a V-neck, rather than leaning to either side.

Choosing the Right Increase or Decrease

As a rule of thumb: reach for a yarn over only when you want the hole to show, use kfb when you're working in a textured stitch where the little bump won't be noticed, and default to M1L/M1R or lifted increases whenever you need shaping to vanish into plain stockinette. For decreases, keep k2tog and ssk as your everyday pair for anything shaped symmetrically, and save sk2p for the moments a pattern calls out a true centered double decrease.

The underlying logic is always the same: figure out whether the shaping should be invisible or visible, and whether it needs to mirror something happening on the other side of the piece. Once you're asking those two questions automatically, choosing between "k2tog or ssk" or "kfb or M1" stops being guesswork and becomes second nature.

Sources

• Examining Knit Decreases: K2tog, SSK, and Sl2-K1,P2sso – tin can knits
• Make 1 Right (m1R) + Make 1 Left (m1L) – Purl Soho
• Decrease (knitting) – Wikipedia)
• Increase (knitting) – Wikipedia)