Fruit of the twine

Tutorial: Using ratios to calculate yardage

Posted by yarnberry on May 21, 2007

Sometimes I’m working on a project, and I want to figure out how many yards of yarn I’ve used to create it. I have to frog the project and measure it, or measure how many yards are left in the skein, right? There’s a much easier way: calculate how many yards I’ve used in the project, using the a kitchen scale and the yarn label.

Here is an example from a slipper pattern I’m working on at the moment. I want to make a second pair, but I’m not sure if I have enough yarn. The slippers shown here were made with a skein of Bernat Super Value Ombres, and I would like to make a pair out of some Schachenmayr Punto Shine.

Measure weight of the object (without needles, buttons, or anything else attached):
= 90 g
Check weight of skein from the yarn label:
= 142 g
Calculate percentage of skein used:
= weight of object / weight of skein
= 90 g /142 g
= 63%
Check yardage of skein from the yarn label:
= 275 yd
Calculate percent of yardage used:
= length of skein * percent of skein used
= 275 yd * 63%
= 174 yd

Remember that this is an estimate. The weight or yardage given on the label might not be quite right, your kitchen scale might not be balanced, you might have a slightly different tension when you make the object again with a different yarn. But it will give you a rough guideline of how many yards you need.

So I need approximately 176 yards of 18st/4″ yarn to make this project again. I only have 110yd of the Punto Shine, so I’ll have to use something else.

Some of you may be wondering why I don’t just calculate how much yarn I need by using the weights. I prefer to calculate project requirements using yardage because the weight of yarns varies so much by fiber content. I find that length requirements are more reliable.


2 Responses to “Tutorial: Using ratios to calculate yardage”

  1. WTL said

    It is like you are speaking another language, but adding in a touch of math to tempt me.


  2. yarnberry said

    We will get you crocheting any day now! Bwahahahaha.

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