What KFB Means and Why You Use It

KFB stands for "knit front and back" — a stitch that turns one loop on your needle into two loops. You use it to increase the width of your knitting without casting on new stitches or picking up stitches from the edge. It is one of the most common ways to add stitches in the middle of a row, and it appears in patterns for sleeves, shaping, and decorative increases.

The stitch creates a small bump or bar at the base of the new stitch, which is visible and sometimes intentional as a design detail. If you want the increase to be less noticeable, other methods exist — but KFB is fast and works well when the bump does not matter or when the pattern calls for it by name.

Key Takeaways

  • KFB means knitting into the front loop of a stitch, then knitting into the back loop of the same stitch before dropping it off the needle.
  • The stitch creates a visible horizontal bar below the new stitch, which is normal and part of the technique.
  • You work KFB on the knit side of your fabric; on the purl side, the equivalent stitch is called PFB (purl front and back).
  • The increase happens in one stitch and takes only a few seconds once you understand the hand motion.

The Basic Steps to Knit KFB

Start with your working yarn in the back and your right needle ready. Insert the right needle through the front loop of the stitch you want to increase — the same way you would for a normal knit stitch. Wrap the yarn around the right needle and pull through to create a new loop. Do not drop the stitch off the left needle yet.

Now insert the right needle through the back loop of that same stitch. You are going in from right to left, behind the stitch. Wrap the yarn around the right needle again and pull through. Now drop the original stitch off the left needle. You have created two stitches from one.

The motion feels awkward the first few times because you are working twice into the same stitch. After a few rows, the hand motion becomes automatic and you will barely slow down.

Where the Visible Bar Comes From

When you knit into the back loop of a stitch, you are pulling yarn through a part of the stitch that was not meant to be worked. This creates a horizontal line or bar at the base of the new stitch. On the knit side of the fabric, this bar sits just below where the two stitches separate.

This bar is not a mistake — it is the signature of the KFB stitch. Many patterns use it intentionally as a decorative element. If you are working a garment where the bar will be hidden (inside a seam, under a fold, or in a textured stitch pattern), you do not need to worry about it. If the bar bothers you, other increase methods like M1 (make one) or lifted increases exist, but they require more steps.

KFB on the Purl Side

If you are working in the round or on a pattern that requires increases on the purl side, the equivalent stitch is PFB (purl front and back). The steps are identical, except you purl instead of knit. Insert the right needle through the front loop of the stitch, purl, leave the stitch on the left needle, then insert the right needle through the back loop and purl again.

PFB creates the same visible bar, now on the purl side of the fabric. The bar will show on the knit side as a small horizontal line, just as it does with KFB.

Common Mistakes and How to Avoid Them

The most common error is dropping the stitch off the left needle too early. If you drop it after the first knit but before you work the back loop, you will have only one stitch instead of two, and the increase will not happen. Keep the stitch on the left needle until both loops are complete.

Another mistake is working into the same loop twice by accident. Make sure you are actually going into the back loop the second time, not the front loop again. The back loop sits behind the front loop; if you are not sure which is which, look at the stitch from the side and notice how the front loop faces you and the back loop faces away.

If your new stitch looks twisted or uneven, you may have pulled the yarn too tight on one of the two loops. Try to keep the tension consistent between the front and back stitches. This becomes easier with practice.

Reading Patterns That Call for KFB

In written patterns, KFB appears as the abbreviation "KFB" or sometimes "K1f&b". If a pattern says "K5, KFB, K5", it means knit 5 stitches normally, then increase one stitch using KFB, then knit 5 more. The increase happens at that exact spot in the row.

In charted patterns, KFB usually appears as a small symbol — often a diagonal line or a square with a dot. Check the pattern's key to confirm what symbol means KFB. If you are unsure, the pattern instructions should list all abbreviations at the beginning.

Frequently Asked Questions

Does KFB always create a visible bar?

Yes. The bar is part of how the stitch works. It will always be visible on the knit side of the fabric, though it may blend in if you are working with dark yarn or a textured stitch pattern. Some patterns use KFB specifically because the bar is decorative.

Can I use KFB to increase multiple stitches in a row?

Yes. If a pattern calls for "KFB 3 times", you work KFB in three separate stitches across the row. Each one creates its own bar. You can also work KFB in consecutive stitches if the pattern requires it, though this creates a line of bars that may look intentional or decorative.

What is the difference between KFB and M1?

KFB works into an existing stitch and creates a visible bar. M1 (make one) creates a new stitch from the yarn between two stitches and is less visible. M1 takes more steps but blends in better. Use whichever method the pattern calls for; if the pattern does not specify, KFB is faster and works fine.

Do I count the new stitch toward my stitch count right away?

Yes. When you finish KFB, you have two stitches on the right needle instead of one. Your total stitch count increases by one. If you started the row with 40 stitches and worked one KFB, you now have 41 stitches.