How to Use a Sock Ruler (A Mathy Post)

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I thought I’d write a quick post to share one of my favorite knitting tools with you.  It’s called a Sock Ruler and you can get one on Etsy (just search for Sock Ruler) or Amazon (check out the 3-pack!).  This is one of those knitting tools that I can’t imagine how I ever functioned without it – it’s so simple, yet so brilliant!

To use your sock ruler, just figure out how long you want your sock to be, then subtract how long your toe will be, then pop the curved end of the ruler into the heel of the sock and knit until you hit the magic number and start your toe.  (If you want to get super clever, you can put a little piece of washi tape on the ruler where you started the toe on the first sock so you remember that measurement for the second sock – like I’ve done on the picture above.)

How Long Will Your Toe Be?

If need help with the mathy parts of using the ruler to get a perfect foot length, it’s easy.  To figure out how long your toe will be, just count how many rows it will take you to do the toe decreases.  Eg. If you decrease from 64 stitches to 20 stitches that’s 44 stitches you need to decrease.  Each decrease rounds removes 4 stitches, so divide 44 by 4 and you know you will need to knit 11 decrease rounds.

If you decrease every other row on your toe, then you’re looking at a 22 row toe.  I like a round toe, so I typically decrease every other row until I have 40 stitches on the needles, then every row until I have 20.  So that would be 6 decrease rows done every other round, and 5 decrease rows done every round, which is 17 rows for my favorite toe shape.

Now measure your row gauge for 1” in stockinette – for me, that’s usually about 11 rows per inch with my favorite brand of sock yarn on my favorite 2.5mm needles.  Divide the number of rows needed for your toe by your number of rows per inch.  That comes out to 2” for a pointier toe (22/11) or 1.5” for a rounder toe (17/11).

Don’t want to do that math? You can cheat.  Most women’s socks I have encountered are designed to have a 1.5” or a 2” toe at the recommended gauge.  You can always just split the difference and knit as if you will have a 1.75” toe.  No one is ever going to notice if the sock measurement is off by 1/4 of an inch.  Plus, the worst case scenario is that you’re wrong and you have to unravel the toe and start over. Not the end of the world. Toes don’t take that long to re-knit.

How Long Should the Foot of Your Finished Sock Be?

Use a foot length chart like this one to select a foot length based on a shoe size.  I’d ignore the suggestion for how long the toe should be on this chart and just consult the last column – total foot length.

OK, that post was a little longer than I intended for it to be.  And there was math.  Sorry about that!  But, seriously, get a sock ruler and get mathy with your bad self. You’ll be happier for it.