How to Design Patterns: Step 2 - Gauge Math

Understanding gauge math is the foundation of pattern design. It's all about using your swatch to unlock key information that will help in creating your pattern. This week, we're diving into how to use gauge math to make your designs a success!

What's Gauge Math?

Gauge math is the process of using the information from your swatch (stitches and rows per inch/cm) to calculate crucial details for your project. It helps ensure your designs turn out the desired size and enables you to calculate the total yarn you'll use.

Determining Stitches and Rows for Your Project

Use your swatch to figure out how many stitches and rows you'll need to make for your desired size. Here's a step-by-step guide including an example:

1. Measure your swatch: Block your swatch, and then count how many stitches and rows fit within the inches/cm.

15 stitches = 4", 18 rows = 4". 

Then, divide the stitches and rows by the width and height to calculate your gauge per inch/cm.

15 / 4 = 3.75 stitches in 1", 18 / 4 = 4.5 rows in 1". 

2. Decide the size of your project: Determine the desired width and height of your project. Be sure to keep everything in one unit of measure. If you measured your gauge in inches, keep your project measurements in inches, and vice-versa with centimeters.

Width of 10", height of 12"

3. Calculate stitches: Multiply your stitches per inch/cm by the width measurements of your project to find the total number of stitches needed.

10" x 3.75 sts/inch = 37.5 stitches. Since we cannot create half a stitch, we round up to 38 stitches to get a width of 10".

4. Calculate rows: Multiply your rows per inch/cm by the height measurements of your project to find the total number of rows needed.

12" x 4.5 rows/inch = 54 rows. This is already a whole number, so we would make 54 rows to get a height of 12".

Calculate Yardage/Meterage

Use this formula to estimate the amount of yarn required for your project:

1. Weigh your gauge swatch: Use a precision scale or kitchen scale to find the weight of your gauge in grams or ounces.

15 stitches x 18 rows = 3.5 grams

2. Get the yarn's information: Look at the yarn's label that you used for your gauge swatch and note down the yards or meters, and grams or ounces. Be sure that you're staying in one unit. If you'd like to calculate the total yardage, note the yarn's yards. If you weighed your gauge in grams, note the yarn's grams.

Yarn's yards: 230
Yarn's grams: 50 grams

3. Calculate the total stitches in the gauge: Find the total amount of stitches in your gauge swatch. You can find this by doing a simple area of a square formula.

15 stitches x 18 rows = 270 stitches in the gauge

4. Calculate the constant: Calculate a constant value that is the number of grams or ounces in one stitch by dividing the weight of the gauge by the total amount of stitches in the gauge. This will result in a very long decimal value.

3.5 grams / 270 stitches = 0.012962963

5. Calculate the total stitches in the pattern: This is the trickiest part. You'll need to calculate the total amount of stitches you'll be making in the entire pattern. This is where you'll use some geometry area skills to figure out the total stitch count. This doesn't need to be absolutely exact, just know that the more estimated the stitch count is, the more estimated the final yardage/meterage will be.

3000 stitches in our pattern

7. Estimate Yardage/Meterage: Now you can finally calculate the total yardage/meterage you will use! To do so, you'll take the pattern's total stitch count, multiply it by the constant and the yarn's yards or meters, then divide it by the yarn's grams or ounces.

3000 stitches x 0.012962963 grams/stitches x 230 yards / 50 grams = 178.89 yards of yarn, or 179 yards

So this is the total yardage/meterage that you will use to create the total specified stitch count with the provided gauge.

Tips for Success

• Always block your swatch before measuring - it changes the gauge, especially with certain fibers.

• Use even tension when working your swatch to replicate how you'll work on the project.

• Make your swatch large enough (at least 4" x 4"/10 cm x 10 cm) for accurate measurements.

• Always measure within 0.25" or 1 cm for precision. A small discrepancy in your gauge can result in a big difference in your final project.

Gauge math might seem intimidating at first. But with practice, it becomes second nature. It's a powerful tool to bring your creative visions to life.

Check out the rest of the How to Design Patterns series to dive deeper into the steps of pattern design!

Have any questions about gauge? Drop them below in the comments, and let’s chat! Don't forget to tag your swatches with #LetsMaeKit and share your progress with us.