Custom Fit Socks

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For anyone living in parts of the world where the temperatures drop below freezing, having good quality warm socks is a necessity for staying warm.  Custom fit socks made of wool help keep your toes warm inside boots and under the bed covers at night.  Sock yarns which are mostly wool are fairly easy to find and it is quick and easy to knit up a pair of socks.  These socks end just above the ankles and only used 1 skein of 227yrd/208m sock yarn to make.

Sock yarn: One skein of 227yrd/208m sock yarn made 2 socks that cover the ankles.  For taller socks you would need 2 skeins of yarn
A set of double pointed knitting needles, US 2 or 3 / 3mm or 3.25mm for sock weight yarn (reference size recommendation on skein wrapper)
String/light weight yarn like crochet thread for the provisional cast on

Step 1) Swatch Your Yarn
Knit a basic swatch of your yarn that is at least 20 stitches wide and at least 15 rows tall.  Take very accurate measurements of this swatch and write down your measurements!


Step 2) Create Your Gauge
To figure out your knitting gauge, you need to make a few quick calculations.


For a swatch which is 25 stitches wide and 15 rows tall, my sample measured 3.25″ wide by 1.375″ tall.
How many stitches per inch is that? Divide the number of stitches by the measurement to find out.
25/3.25 = 7.69 which equals about 8 stitches per inch.

Determine how many rows per inch in the same way.  Divide the number of rows by the measurement.
15/1.375 = 10.9 which equals 11 rows per inch


For a swatch which is 25 sts wide and 15 rows tall, my sample measured 8.3 cm wide by 3.5cm tall.
How many stitches per centimeter is that? Divide the number of stitches by the measurement to find out.
25/8.3 = 3.01 which means you will have 3 stitches per centimeter.

Determine how  many rows per centimeter in the same way.  Divide the number of rows by the measurement.
15/3.5 = 4.3 which means you will get 4 rows per centimeter.


Step 3) Measure Your Foot
To make custom fit socks, you need 2 measurements of your foot.


Measurement 1: Measure around the widest part of your foot.  You may want to measure in a couple spots to find the right measurement.  I measured around the ball of my foot and the widest part of the arch.


Measurement 2:  Measure the length of your foot on the sole from the longest toe to the heel.

These measurements will be used a couple ways and at different times so be sure to write them down.


Step 4) Determine Your Sock Gauge
You will be knitting in the round to make this sock working from the toe to the heel.  You need to know how many stitches it takes to go around your foot – but some will be removed for a snug fitting sock.  This is when you will use the around the foot measurement and your stitches per inch/cm information.
Using my foot for example…
My foot is 9.375″ / 24cm
My sts per inch: 8, per cm: 3


Foot measurement multiplied by stitches per inch:
9.375 x 8 = 74 (actually 75 but you want an even number so subtract 1 stitch)

Foot measurement multiplied by stitches per cm:
24 x 3 = 72


For a snug fitting sock, remove 20% of the stitches.  Multiply the number of stitches by 0.8:
74 x 0.8 = 59.2 stitches.  And you are almost there.


Round to the closest number which when divided in half is an even number.
If you round to 58, half of the number is 29.
If you round to 60, half of the number is 30.  <- This even number is what you are looking for.


Step 5) Provisional Cast On
Cast on half of the needed stitches onto one needle using the provisional cast on method.
See the post on provisional cast on for how to do this.


Step 6) Create the Sock Toe
To create the clean smooth toe of comfortable socks, use the wrap and turn techniqueSee the post on wrap and turn for how to do this.  You will want to work down to 50% of the cast on stitches.  If you did a provisional cast on of 30 stitches, 50% equals 15 stitches but you don’t want an odd number (you’ll end up with a lop-sided toe) so work down to 14 stitches.


After your toe is worked, you’ll have something that looks like this.
Wrap and Turn Sock Toe

Work the stitches from the provisional cast on onto a second needle.  Take care to not split your yarn while you are doing this and double count your stitches to ensure you didn’t accidentally miss or drop a stitch before removing the string.
Wrap and Turn Sock Toe

At this point you should have the correct total number of stitches on your needles that you determined to need in step 4.
Wrap and Turn Sock Toe


Step 7) Measure the Wrap and Turn Toe
At this point you will take the measurement of the toe.  To create the heel of the sock you will use the same wrap and turn technique and knowing this measurement is crucial to making a successfully fitting sock.
Wrap and Turn Sock Toe


Step 8) Determine the Sock Length
At this point you have a completed sock toe.  You will need to knit in the round until working the heel of the sock.  How many rows do you need to knit before beginning the heel?


Pull out your notes from measuring your foot length.
Again using my foot for example…
My foot is 9″/23m long.
The wrap and turn toe is: 1.5″/3.8cm


You will do a wrap and turn for the toe and the heel therefore you need to remove that length from the total sock length for the correct fit.
Foot length – toe – heel = arch length to knit
9″ – 1.5″ toe – 1.5″ heel = 6″ to knit
23 – 3.8 toe – 3.8 heel = 15.4cm to knit


Using your row gauge to determine how many rows to knit:
6″ x 11 rows = 66 rows
15.4cm x 4.3 = 66 rows
Optional: For a snug fit you can choose to remove 10-20% from the length as well.


Step 8) Knit the Arch of the Sock
Work the stitches of your sock onto 3 needles.  Use a stitch marker to indicate the start of your row (I used a small piece of crochet thread).
Custom Fit Sock


Knit the arch of your sock.


Starting at the beginning of the row, place half of the stitches onto one of the needles.
Custom Fit Sock

Work the wrap and turn technique again to create the heel.  Work down to 50% of the stitches in the say way you worked the toe and then back to the original number of stitches.
Wrap and Turn Sock Heel


Step 9) Finish Sock to Desired Height
After completing the wrap and turn for the heel, continue knitting in the round until the desired height of the sock is achieved.  At this point your personal taste dictates the look of the sock.  It can be ankle high, mid leg, knee high, or thigh high.  I worked until I ran out of yarn, being careful to ensure both socks ended at the same height.  After a few rows of stockinette I switched to 2×2 rib knit for a closer fit at the ankle.


Step 10) Casting Off
For socks, I recommend using this cast off technique for a stretchier cast off. See post on casting off your knitting with a stretchier cast off.


These warm socks will make the cold weather so much easier to bear.