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Loom Knit Mitered Square Calculator

Loom Knit Mitered Square Calculator

“Why, oh why, does it look like a kite?!?”

If you ever tried to loom knit a mitered square just by converting the needle knit pattern you may have screamed the same thing when you finished.

There’s a reason why sometimes a mitered square done on a loom comes out perfectly and sometimes it doesn’t.

What is a mitered square?

Traditional mitered squares are created by casting on two sides of the square. Then as you work in garter stitch you decrease in the middle of every other row causing the two sides to pull in toward each other along the center diagonal. You continue decreasing until you have one stitch left then finish off at the corner.

It’s an amazing design when worked in stripes (as you’ll see later on) because the stripes change direction.

loom knit mitered square example
Anatomy of a Mitered Square

Why can’t I just translate a needle knit pattern?

In needle knitting garter stitch means you knit every row. That means you’re always working the same stitch for the whole project. All your knit stitches will be the same size as long as you keep your tension consistent.

However, on a knitting loom you work garter stitch by knitting one row and purling the next. You are making two unique stitches that may or may not be the same size (width and height). And we can’t ignore that there are multiple versions of the knit stitch to choose from giving you even more size differences.

This is why sometimes a loom knit mitered square is an actual square and sometimes it looks a kite and arrowhead and sickly manta ray.

loom knit mitered square fail kite-shaped
Uh oh! That’s no square!

So, how do I solve the issue?

Years ago on a loom knitting discussion board I came across a conversation that addressed this problem and how to fix it. Brenda Myers and Denise Layman were instrumental in analyzing the underlying issues and working out the math to figure out a solution.

This calculator builds on their early work. I used Brenda’s formula for calculating the ratio I needed to work out a mitered square. Then my brain flipped the numbers all around and I ended up with a shape that was nothing like a square.

Then I called my math whiz, Joann.

She took the formula and tested it to come up with a way to provide you with the correct pattern without you having to process (or even understand) the math yourself.

How accurate is the calculator?

Is it a total customized pattern? Well, no. But I found after much testing with various yarns and looms that the size ratio fit into one of 3 groups.

Because of that I wrote 3 different patterns each spacing out the decreases differently. You personal tension will fit into one of the pattern ranges and I am confident that you will be able to loom knit an actual square. It may vary slightly, but with some light blocking it’s square and not an odd shape.

loom knit mitered square calculator test swatches
Test swatches galore! Thanks to my test knitters!

What do I need to use the calculator?

The calculator uses measurements from a small swatch. (I know, I know. Nobody likes swatching.)

Loom knit a small swatch in garter stitch using the loom and yarn for your project. Make sure you use the same knit stitch you plan to use for your final project. You swatch should be at least 4-6″ wide and long. You don’t need to bind off unless you want to. I cut my working yarn long and just pulled it through all the stitches on my pegs.

Next, give that swatch a workout! Pull it in several directions and shake it out to allow the stitches to relax. You do not want to measure your swatch right off the loom.

Then, measure the width and length of your swatch along with the total number of stitches and rows (not counting the cast on/bind off) and enter those into the calculator. Measure to the nearest 1/8″ (or mm if using metric).

Lastly, enter the size you want your finished square.

The calculator will tell you how many stitches to cast on and which of the 3 patterns of the Loom Knit Traditional Mitered Square pattern you should use.

Don’t worry I have a handy video at the bottom of the page to walk you through.

loom knit mitered square calculator pin image

Loom Knit Mitered Square Patterns

How to use the Loom Knit Mitered Square Calculator:

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Tuesday 11th of August 2020

Just starting to learn loom knitting your video are very helpful thank you.