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Our last thrilling installment was a recipe for inserting a flap-and-gusset heel into any cuff-down sock pattern.  Today, we approach that heel from the other direction.

The following is a recipe for a flap-and-gusset heel that you can plug into your favorite toe-up sock pattern. It’s easy and fun, and I’m very fond of it.

Map of a Heel

start at the toe, and knit the foot first. then the fun begins.

The Gusset

This bit’s an easy conversion: instead of decreases at the edges of the sole, you work increases.

When the sock is the right length (see below for calculations on placement of the heel), work as follows:

In this recipe, the instep is the first half of the round, and the sole is the second half.

Gusset round 1.  Set up markers for heel. Work across instep in pattern. M1R, place a removable marker on the needle, k to end of sole sts, place a removable marker on the needle, M1L. 2 sts increased.

It’s easier if you keep the increases grouped together with the sole stitches. The markers are there for two reasons: to help you keep count of the gusset stitches, and to guide you with the heel turn. You’re not working the increases beside the markers, as you might think, but at the very ends of the sole stitches. Removable markers make the first row of the heel flap a little easier.

Gusset round 2. Work across instep in pattern, k to end of round.

Gusset round 3. Work across instep in pattern, M1R, k to end of round, slipping markers when you come to them, M1L. 2 sts increased.

Gusset round 4. Work across instep in pattern as set, k to end of round.

Repeat rounds 2 and 3 until you’ve increased to the required stitch count.

Your gusset will look something like this.

What is the required stitch count? See below for information on how to decide.

Begin the Heel Turn

My preferred toe-up heel is heavily inspired by the work of Wendy Johnson.

We begin with what is, effectively, the first step of a short-row heel. It creates a tidy round under the back of the heel.

Note: I’m using German Short Rows for this as I think they’re somewhat easier to do than a traditional wrap and turn, and they are significantly easier to make tidy.

With a wrap and turn, you make a wrap around a specific stitch and turn your work. With German Short Rows, the steps are slightly different. Instead of putting a wrap around a stitch, you work it—knit or purl as appropriate.

Work the stitch that would have been wrapped.

Then turn your work. Then you create a doubled stitch, abbreviated as DS.

To do this, first slip the stitch just worked purlwise wyif.
Then tug on the working yarn so that it pulls the just-slipped stitch up onto to the needle, so that both legs of the stitch are on the needle; keep tugging and take the working yarn over the needle into position for the next stitch.

In the instructions below call this process “make DS” in the instructions below.

This doubled stitch is the stitch that would have been wrapped in the wrap and turn.

The Heel Turn

Heel turn row 1 (RS). Work across instep in pattern as set; k to last marker, turn work.

Heel turn row 2 (WS). Make DS, p to marker, turn work.

Heel turn row 3. Make DS, k to DS, turn work.

Heel turn row 4.  Make DS, p to DS, turn work.

Each time, you’re working one stitch less, making the new DS beside the previous one.

Work back and forth until about a third of the heel stitches remain unworked in the center, ending with a WS row. With RS facing, count your DS. You should have one more DS on the left side of the heel than on the right. The “missing” DS will be made in the first row of the heel flap.

Once it’s there, it will look like this:

The Flap

In the first two rows, you’ll knit or purl each DS you created. It’s actually very simple: just work into the stitch as normal, catching both legs of the DS.

On the left needle: a DS ready to work.
And that’s all there is to it.

Heel flap row 1 (RS). DS, k to 1 st before the gusset marker. Remove the marker from its existing position and place it here. (You’re moving it one stitch to the left.) SSK, turn. 1 gusset st decreased.

Heel flap row 2 (WS). Slip 1 pwise wyif, p to 1 st before the gusset marker. Remove the marker from its existing position and replace it here. (You’re moving it one stitch to the left.) P2tog, turn. 1 gusset st decreased.

Heel flap row 3 (RS). Sl 1 pwise wyif, slip marker, k to second marker, slip marker, ssk, turn. 1 gusset st decreased.

Heel flap row 4 (WS). Slip 1 pwise wyif, p slip marker, k to second marker, slip marker, p2tog, turn. 1 gusset st decreased.

Repeat heel flap rows 3 and 4 until 1 gusset st remains on each side.

The flap is nearly done.

You might expect to just continue until all the gusset stitches are decreased, but I find that doing this makes for a gap on either side of the heel. It’s much better if you work the final two gusset stitches in the first round of the leg, as follows.

First round of leg. Sl 1 pwise wyif, remove marker, k to second marker, remove marker, ssk; work across instep in pattern as set; k2tog on last gusset st and first heel flap st, k to end of heel.

The start of round is positioned at the start of the instep. You’re back to working in the round and can finish the leg as you wish.

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Notes on Heel Placement

Here’s the rub to this heel: you have to work out exactly when to start the process, to make sure the foot turns out to be the right length.

It’s not difficult, but requires two (possibly surprising) steps.

Step 1: Measure Your Round Gauge.

When you’ve worked about two inches past the toe, slip the sts to scrap yarn (or the cord of your magic loop) and soak the sock in lukewarm water for 10 or 15 minutes. Squeeze the water out and the let it dry overnight.

Once it’s dry, measure your round gauge: count the number of rounds in 2 inches, and divide that by 2, to get the number of rounds in one inch.

A swatch gauge comes in handy here. I’m getting 12 rounds per inch.

Step 2: Work Out How Long Your Gusset and Heel Will Be.

Decide how many gusset stitches you want. For the average adult foot, I suggest 20% of the overall sock stitches, on each side.

My usual sock has 56 stitches. 56 x .2 = 11.2, which I round down to 11.

This means that I’ll have 22 rounds in my gusset, because each increase round is followed by an even round. And at 12 rounds per inch, that’s going to take up 22 ÷ 12 = 1.83 inches.

Next you need to work out how long the heel is. For this, multiply the number of heel stitches by 2/3, and round the result down to the nearest even number. (Put another way, you’re calculating the number of rows you work back and forth until the central third of the stitches are unwrapped.) For my 56-stitch sock, my heel stitch count is 28, and 28 x 2/3 = (28 x 2) ÷ 3 = 56 ÷ 3 = 18.667, which I will round down to the nearest even number. This is the number of rows in the heel turn.

And 18 rows at 12 rounds per inch, that’s going to take up 18 ÷ 12 = 1.5 inches.

What does this mean? Add those together lengths, and that’s how much space you need for the gusset and the heel turn. For me, at this gauge, with these numbers, my heel and gusset will take up 1.83 + 1.5 inches = 3.33 inches.

Then I work the foot in the round until it measures the desired foot length minus that much.

My foot is 9 inches long, so once the toe increases are complete I’m going to work the sock foot until it’s 9 – 3.33, or 5.67 inches long. At that point, I’ll start the gusset.

You’re Asking Me To Do What?

If you’re still with me at this point, you’ll have realized that for all the fun and advantages of toe-up sock knitting, the trade-off is that you need to do a quick bit of measurement and arithmetic. If you don’t, the risk is that the heel turn won’t hit in the right place, and your sock foot could come out too short or too long, neither of which is desirable. The good news is that you only need to do this on the first sock. For the second one, just keep track of the rounds and make sure you match the first.

Whether this is a deterrent or not is up to you. The alternative—working from the cuff down—isn’t entirely measurement free. You do have to decide when to start the toe.

I think it’s worth trying the flap-and-gusset heel in a toe-up sock. If the short-row heel doesn’t work for you, this structure offers an improved fit, and the flexibility to fine-tune it.


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About The Author

Kate Atherley is a teacher, designer, author and technical editor. She’s also the publisher of Digits & Threads, a magazine all about Canadian fibre and textile arts.


  • Kate, you’re the best! Thank you very much for these incredibly timely and helpful tutorials. Now, let me look at that new sock yarn…..

    • Thank you for this recipe! It worked perfectly! I thought the math was complicated, and I tried to simplify the calculations for my future projects. I thought I would share this with you, for people who hate math, because I think toe-up socks are awesome, and should be encouraged!

      Basically, I think a close approximation of the length needed for the heel is to take 73% of the total sock stitches, and divide that by your round gauge. This is based on your recommendation of 20% of total stitches for each side of the gusset. For your example of 56 stitches, this would be 3.41 inches, which is very close to the 3.33 inches in your example.

      This number you would subtract from your foot length to get how long the sock should be before you start the gusset.

      Then you would need to calculate 20% of your total stitches to get how many stitches you increase on each side of the markers for the gusset ( or multiply that x 2 for number of gusset rounds).

      Showing my work: 20% x 2 = 40%, which accounts for the gusset increases.
      For the heel stitches, 2/3 of the heel stitches equals 1/3 of the total stitches, as shown in your calculations, which is about 33 percent. 40% + 33% of total stitches = 73%. For 56 stitches, this is 40.88. (56 x 0.73). Then you divide this by the row gauge, for the inches to be subtracted from foot length

      Of course this only applies if you are using the 20% recommendation for gusset stitches which worked perfectly for me!

  • Thank you for this. Flap and gusset heels work best for most of the feet I knit for (we are a very high instep tribe) and this will make it easy to convert patterns with short row heels. Your German short row description is quite clear but, if anyone would find a video helpful, Melanie Berg has a fabulous one. It is linked on her Ravelry site. Go to her pages section and then links to knitting techniques. I am sure there are other great videos on this out there but I return to this one every time I need a quick refresher.

  • Since gauge changes with different yarn, mood, and who knows, maybe sun spots, do you check your rounds gauge like this on each pair of socks you knit??

    • I don’t. The “right” answer is that you should, but ~3-3.5″ is about right for most fingering weight sock yarns, and then it comes down to personal preference on how snugly you want your heel to fit. One row off isn’t going to appreciably change how your sock fits unless you’re VERY picky. If you’re using a totally different weight of yarn than you usually do, for sure check.

      • Not to be boring, but the challenge is that the length required varies also based on how many gusset stitches you’re working, so it’s not quite as easy as it seems…. It can vary more than you expect!

      • Thanks! Truly love that the answer is yes/no/ymmv.v Thanks for this — gonna try it on the WIP.

    • Ha! Yes, you’re right about sun spots. Yes, you do need to check round gauge on toe-up socks. I always check after I’ve worked about an inch beyond the toe.

  • I am confused. Heel flap row 1 &2, if I work to one stitch before the marker, am I not moving the marker one stitch ‘right’ not as written ‘left.’

    • I have this question too.

      • Ok I’ve worked out what this means for anyone like me who gets confused by this. Where it’s written “Remove the marker from its existing position and replace it here”, ignore the last four words for now. Just get to the point where there’s one DS on the left needle, remove the marker, SSK the last DS together with the next regular stitch, and replace the marker. Then turn.

    • Question: on the hell flap toss, when you are doing SSK or K2tog, is each DA considered one stitch? So you are actually knitting two double stitches together?

      • I’ve tried all sort of things. Double knitting colour work cables and more. I’m not fearful of new thing but………..You have all just convinced me that knitting socks is out of the question. All this work and math and washing and in the end it may not fit the foot. Sorry, not for me. I was tempted until I read these comments.

      • Hello! Each double stitch is considered a single stitch. You’re only working decreases with double stitches on the first two rows, if that helps?

  • I use a flap and gusset heel on toe-up socks all the time as they fit really well. I use shadow wrap short rows though. I have tried German short rows and find them very fiddly.

  • Great article, thank you. BUT, I have one question. Is negative ease not a factor in your foot length?

    • The negative ease happens nicely as a side effect of how the heel curves around foot. Usually it’s just fine, but if you wish you can shorten the foot a tiny bit!

      • I’m confused. Do we subtract our final length of the heel and gusset calculations from the real foot length or from the foot length times .95?

    • I was going to ask this, too! I though about 1/2″ of negative ease is preferred for the sock length, but that may be what I’ve been doing wrong. My Toe-Up Gusset socks seem to always be just a tad short even though I do the calcs each time.

  • Thank you! Thank you! This is exactly what I needed.

  • Thank you for this tutorial. I have your Custom Socks book and I am using it to teach myself toe up socks that fit ! I was confused by the gusset markers because I was using short circulars . I put them back on dps and with the help of your pictures I’m making progress !

  • Thank you for this! I wrote some javascript for a calculator to help me do the math – I’m happy to send it to you if you’d like use it for something.

  • Thank you for these explanations, I used them to knit my first heel flap sock, and it fits much better than short row heels ! (less tight).

    I think I spotted a mistake though, in the Heel flap row 4 (WS) section. You write “k to second marker”, but you must mean purl, since the heel in your picture is in stockinette, not garter stitch.

    Another question : in row 3 of the heel flap, you say to slip the first stitch with the yarn in front. Is there a purpose to keep the yarn in front rather than inside the sock?


    • Hi I had the same question too – when I get to that point I’m going to decide to knit or purl…

    • I had this question on the heel flap as well. On both RS and WS (Rows 3 and 4) it says to knit the stitches. Should row 4 be purl?

  • Thank you for the “where to start gusset” calculations! I never get round guage and am either trying to work out the ratio of my guage to theirs and calculate the difference or ripping out multiple times to get it right. Now I can calculate and stitch with confidence! Thanks again 🙂

  • Hi Kate, I have your book Custom Socks and would like to know if I can use the Heel/Gusset Length you provide in your tables for the German Short Rows (as all instructions and patterns in the book use Wrap&Turn short rows). Thanks.

  • Wow so helpful, thanks so so much I found your pattern, im kitting my husband sock and his food nearly 12’’ so can’t find the pattern for that huge sock. Thank you again and hope i can knitting sock

  • Yikes……. Lots of measuring, etc. I have done gusset heels by Wendy’s toe up books. I love toe up, taat. Almost always do FLK heels….. might give this a try. Ps. I have Wonderlust….have made couple pr of lovely socks from it.

  • Is Heel Flap row 4 correct? Shouldn’t it read: ….P to second marker?

  • It would be extremely helpful if you would provide a print option so especially useful articles could be easily saved on my computer. Thank you!

  • “You might expect to just continue until all the gusset stitches are decreased, but I find that doing this makes for a gap on either side of the heel. It’s much better if you work the final two gusset stitches in the first round of the leg, as follows”

    If I want to use this on a bought pattern, isn’t my flap then two rows to short? Because normally I would knit two rows where I would decrease those two last gusset stitches. If I don’t do this to follow your trick where I decrese those on the first round of the leg I’m missing those two rounds in the flap. How could I solve this please?

  • I love this until Heel Flap Row 1 (RS). You say to make a DS, but what happens to it then? It doesn’t seem to show in the picture. Do I knit the DS as the first stitch in this row? Or do I slip it to the right-hand needle and then proceed to knit the single stitches? Help?

  • This is great… but I agree with others there are some errors (heal flap row 4) and some confusing directions (heal flap row 1).

    It would be great if MDK could correct this. If folks don’t read ALL the comments, they’ll make mistakes, tear their hair out, give uo.

  • This is great… but I agree with others there are some errors (heal flap row 4) and some confusing directions (heal flap row 1).

    It would be great if MDK could correct this. If folks don’t read ALL the comments, they’ll make mistakes, tear their hair out, give up.

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