What knit front and back does, and when you use it

Knit front and back (often written as KFB) is a method of increasing — turning one stitch into two stitches on the same row. You knit into the front loop of a stitch the normal way, but instead of dropping it off the needle, you leave it on. Then you knit into the back loop of that same stitch and drop it off. You now have two stitches where there was one.

This increase is useful when you need to add stitches gradually across a row — for shaping sleeves, adding width to a sweater body, or creating a subtle increase line that blends into the fabric. Because you're working into the same stitch twice, the increase sits slightly to the right and creates a small visible bump. Some knitters use this on purpose as a decorative element; others hide it by working it on a purl row or inside a seam allowance.

KFB is different from other increases like yarn overs (which create a hole) or lifted increases (which pull a stitch from the row below). It's one of the most common increases in patterns because it's fast and doesn't require dropping stitches or managing extra yarn.

Key Takeaways

  • Knit front and back means knitting into the front loop of a stitch, then the back loop of the same stitch before dropping it off the needle.
  • The increase creates a small visible bump on the right side of the fabric, which you can hide by working it on a purl row or inside a seam.
  • This method adds one stitch per KFB and works on any row — you don't need to plan ahead or manage extra yarn like you do with yarn overs.
  • The stitch you create from the back loop may twist slightly; some knitters deliberately twist it the opposite way to keep the fabric even.

Step-by-step: How to knit front and back

Insert your right needle into the front loop of the stitch you want to increase, the way you normally would for a knit stitch. Wrap your yarn around the needle and pull the new loop through — but do not drop the original stitch off the left needle yet. Leave it sitting on the left needle.

Now insert your right needle into the back loop of that same stitch. Go in from right to left, behind the stitch. Wrap your yarn and pull a new loop through. This time, drop the original stitch off the left needle. You now have two new stitches on your right needle, both created from the same original stitch.

The whole motion takes about two seconds once you've done it a few times. The key is remembering not to drop the stitch after the first knit — that's the part that trips up new knitters.

Why the back loop stitch may look twisted

When you knit into the back loop of a stitch, you're working it in the opposite direction from normal. This can make that stitch sit slightly twisted on the needle. On the next row, it may look a little off compared to the stitch you created from the front loop.

If this bothers you, you can compensate by deliberately twisting the back-loop stitch in the opposite direction as you create it — essentially un-twisting it. This takes a bit of practice and isn't necessary for most projects, but it does create a more even-looking increase. Many knitters don't bother and find the difference disappears once the fabric is worn or washed.

Where to place KFB in your pattern

Patterns usually tell you exactly where to work KFB — often one or two stitches in from the edge, or spaced evenly across a row. If you're designing your own increases, place them where they won't show or where you want them to show on purpose.

On the right side of stockinette stitch, KFB creates a visible bump. If you want to hide it, work the increase on a purl row (the wrong side), and the bump will sit on the back of the fabric. You can also work it inside a seam allowance — for example, one stitch in from the edge on a sweater body that will be seamed later.

If you're increasing on both sides of a piece (like a sleeve), you might work KFB one stitch in from the edge on both the left and right sides. This keeps the increases symmetrical and slightly hidden in the seam.

KFB versus other common increases

A yarn over creates a hole in the fabric and is the fastest increase — you just wrap yarn around the needle with no extra stitch work. It's visible by design and used for lace patterns. KFB, by contrast, is solid and doesn't create a hole.

A lifted increase pulls a stitch from the row below and knits it, adding one stitch without creating a visible bump. It's slower than KFB and requires more precision, but it blends in better. A make-one increase (M1) is similar — you create a new stitch from the gap between two stitches. Both of these are less common in basic patterns than KFB.

For most everyday shaping, KFB is the default because it's fast, reliable, and doesn't require you to think ahead. Yarn overs are for lace. Lifted increases and make-ones are for when you want an invisible increase or a specific stitch pattern.

Common mistakes and how to fix them

The most common mistake is dropping the stitch off the left needle after the first knit. You'll end up with only one new stitch instead of two, and your increase won't happen. If you catch this right away, just put the original stitch back on your left needle and knit into the back loop.

Another mistake is knitting into the back loop too loosely, which creates a sloppy stitch. Keep your tension even — the back-loop stitch should be the same tightness as the front-loop stitch. If the back loop is hard to access, make sure you're going in from right to left, not left to right.

If your increases look uneven across a row, you may be placing them at different distances from the edge or spacing them unevenly. Count stitches carefully and mark your increase points with stitch markers if the pattern doesn't specify exactly where they go.

Frequently Asked Questions

Can I do KFB on a purl row?

Yes. Purl front and back (PFB) works the same way — purl into the front loop, leave the stitch on the needle, then purl into the back loop and drop it off. This is useful when you want the increase to sit on the wrong side of the fabric, where it won't show on the finished piece.

Does KFB create a hole in the fabric?

No. KFB creates a solid increase with a small visible bump. If you want a hole (for lace or eyelet patterns), use a yarn over instead. KFB is solid and blends into the fabric, especially if you work it on a purl row or inside a seam.

What if I can't fit my needle into the back loop?

The back loop can be tight, especially in tight-gauge knitting or with thin yarn. Make sure you're inserting your needle from right to left, not left to right. If it's still stuck, loosen your tension slightly on the previous row, or use a needle one size smaller to create the back-loop stitch and then switch back to your regular needle size.

Do I need to twist the back-loop stitch to make it look even?

Not unless you want to. Most knitters don't bother, and the difference is barely visible once the fabric is finished. If you're making a garment where the increases will be very visible (like a shawl with increases as a design feature), you might want to experiment with twisting to see if it looks better to you.