Why Increases Matter
Every time a knitting pattern tells you to add stitches — shaping a raglan sleeve, widening a hat brim, increasing from cuff to body in a top-down sweater, working a lace motif — it is using an increase. There are several different methods, and they are not interchangeable. The method you choose affects how the increase looks, how much it stretches the fabric, whether it leaves a decorative hole, and how it interacts with the fabric on either side.
Most knitting patterns specify which increase to use. But understanding why a designer chose a specific increase — and what each one looks like — makes you a more confident pattern reader and a better problem-solver when things do not go as expected.
M1L and M1R: The Invisible Increases
M1L (Make 1 Left) and M1R (Make 1 Right) are the most commonly used increases in modern knitting patterns because they are virtually invisible in the finished fabric. They work by lifting the horizontal bar that runs between two stitches — the strand connecting the last stitch on the right needle to the first stitch on the left needle — and knitting into it to create a new stitch.
M1R (Make 1 Right — leans right):
- Insert the left needle tip from back to front under the horizontal bar between the last stitch worked and the next stitch on the left needle. The bar is now on the left needle, with its right leg in front.
- Knit this lifted bar through the front loop. Because you lifted it from back to front, knitting through the front loop twists the stitch closed, preventing a hole.
The resulting stitch leans to the right.
M1L (Make 1 Left — leans left):
- Insert the left needle tip from front to back under the horizontal bar between the last stitch worked and the next stitch on the left needle. The bar is now on the left needle, with its left leg in front.
- Knit this lifted bar through the back loop. Knitting through the back loop twists the stitch closed.
The resulting stitch leans to the left.
When to use M1L/M1R:
Use these for any shaping where you want the increase to be invisible: raglan lines, yoke increases, sleeve shaping, waist decreases-then-increases. In patterns that use paired increases (one leaning left, one leaning right, placed symmetrically), M1L and M1R create perfectly mirrored shaping lines. When a pattern says "increase 1 stitch" without specifying method, M1L or M1R is almost always the right choice for a neat result.
KFB: Knit Front and Back
KFB (knit front and back, also called a bar increase) is older and simpler than M1: you knit into a stitch normally but do not slip it off the left needle. Instead, you swing the right needle to the back of the same stitch and knit through the back loop, creating a second stitch. Then you slip the original stitch off. One stitch becomes two.
The distinguishing feature of kfb is the small purl bump it leaves on the right side of the fabric, immediately to the left of the increase stitch. This bump is visible. In a carefully designed piece, kfb increases are often placed one stitch in from the edge so that the bump becomes a deliberate vertical design element rather than a random mark.
When to use kfb:
- When speed matters more than invisibility: kfb is faster than M1 because it does not require locating and lifting the bar between stitches
- When the increase position needs to be easily countable: the purl bump makes each kfb visible and easy to count in a dense fabric
- In patterns that explicitly specify kfb, particularly older patterns and many sock patterns
- When you want a distinctive ridge or line of small bumps as a design element
Do not use kfb when the pattern calls for M1 — the bump will be visible and was not part of the design. When in doubt about which increase to use, choose M1.
Yarn Over (YO): The Decorative Increase
A yarn over creates a new stitch by simply wrapping the yarn around the right needle before working the next stitch. It leaves a deliberate hole — an eyelet — in the fabric. This is intentional in lace patterns, where the eyelet is the design. In shaping contexts, the eyelet is usually not desired.
Yarn overs are directional and depend on whether the surrounding stitches are knit or purl. Between two knit stitches: bring the yarn forward between the needles, then knit the next stitch. Between a purl and a knit: the yarn is already forward from the purl; simply knit the next stitch. Between a knit and a purl: bring the yarn forward, then wrap it over the needle to the back before purling. Between two purls: bring the yarn over the needle to the back, then forward again before purling.
When to use a yarn over:
- In lace patterns, where the eyelet is the point
- In eyelet patterns and decorative motifs
- As a buttonhole (a yarn over paired with a decrease leaves a clean hole)
Do not substitute yarn over for M1 in shaping contexts — the eyelet will be visible and distracting.
Lifted Increase (RLI and LLI)
The lifted increase — right leaning (RLI) and left leaning (LLI) — is another invisible increase that works by lifting and knitting the stitch of the row below. It is even more invisible than M1 in some fabrics because it does not create a bar stitch.
RLI (Right Lifted Increase):
Insert the right needle tip into the right leg of the stitch directly below the first stitch on the left needle. Lift this stitch onto the left needle and knit it. Then knit the stitch on the left needle normally.
LLI (Left Lifted Increase):
Knit the next stitch on the left needle. Then insert the left needle tip from back to front into the left leg of the stitch two rows below the stitch just knitted (on the right needle). Knit this lifted stitch.
Lifted increases are slightly more complex to execute but the result is exceptionally smooth and invisible. They are particularly useful in very fine yarn or in areas where any stitch irregularity would be conspicuous.
Comparison Summary
- M1L/M1R: Invisible, directional, from the bar between stitches. Best for most shaping.
- KFB: Leaves a small purl bump, fast to execute. Good for sock gussets, brim increases, quick projects.
- Yarn Over: Creates a deliberate eyelet. For lace, decorative patterns, buttonholes.
- RLI/LLI: Extremely invisible, from the stitch below. Best for fine work or when M1 is still too visible.
Paired Increases and Mirrored Shaping
When a pattern uses increases on both sides of a center stitch or both ends of a needle — raglan lines, symmetrical yoke shaping — it uses paired increases: one left-leaning and one right-leaning, placed symmetrically. M1L with M1R is the most common pairing. RLI with LLI also pairs naturally. KFB does not have a natural paired lean, which is one reason it is falling out of use in sophisticated patterns.
If your pattern says "increase 1 stitch on each side" without specifying method, use M1R at the right-side edge and M1L at the left-side edge (or vice versa, depending on which shaping line you want). This creates the cleanest, most intentional-looking result.