Sock Math is necessary to have a nice fitted sock.
Use this sock chart to help determine average measurements for socks for: Premie, Newborn, Infant, Baby, Toddler, Child, Teen, Woman, Man, Adult. Then knit up a swatch with the yarn you want to use in the main stitch pattern.
Be sure to use the needles or loom intended. Knit a 3×3 swatch and measure 2″ across. Divide that number by two for your “gauge”. For help on measuring a swatch see our article. For Loom Gauge to Needle Gauge see this article (hint if converting from needle pattern you’ll need this).
Use our NEW Interactive Sock Calculator and we’ll crunch the numbers for you!
Sock Math for knitters:
1. Measure around ball of your foot (at widest part near toes) with foot resting on it’s weight.
2. Multiply the measurement you took in Step 1 by your stitch gauge (# of stitches in 1″). (Gauge is determined by measuring a swatch made with intended yarn and tools).
3. Multiply this number by .90. This step subtracts 10% to create negative ease. Negative ease is what allows the sock the stretch over your foot giving a fitted sock.
4. Round the result from Step 3 to the nearest even whole number. The result is the number of stitches to cast on.
Example for size 12 women’s feet:
1. Measurement of ball of foot: 9.5″
2. Ball of foot times stitch gauge: 9.5″ x 7 = 66.5
3. Result from #2 with negative ease adjustment: 66.5 x .90 = 59.85
4. Round stitches to nearest EVEN whole number: 60 pegs cast on
(Click image to see larger image.)
**If you need to determine cast-on stitches or rows to knit please use our calculator in our app, or the following formula. For further instructions refer to our blog on calculating from a swatch.
Cast-On Formula used:
Swatch is S stitches and measures W wide. The stitches per inch is S/W and desired width is dW. The Stitches to Cast-On = (dW x S/W).
Now for the Rows Calculations:
Measure the swatch number of rows and enter the number of rows and the measured length. Then enter the desired length of project and press ‘Rows needed are->’.
Formula for rows needed = (dL x R/L) where dL is desired length, R is number of measured rows and L is length measured.**