Can I just knit a bigger size instead?

Last week, two knitters wrote to me with exactly the same question. They had DK weight yarn in their stash - something medium thin, around 50 g and 125 m. But the sweater pattern they loved was written for aran weight yarn, more medium thick, around 50 g and 75 m.

And both asked the same thing: Can I just knit a bigger size instead?

The short answer is yes. But when you switch from DK to aran, it usually means choosing 3 or even 4 sizes bigger. It really depends on how much thinner your yarn is.

Today I want to show you a simple method to check if a knitting pattern will work with thinner yarn. And even if this method does not fit your current project, it is a very useful skill to have. Once you understand it, you will look at yarn and patterns with much more confidence in the future. 🙂

Why this method is special
You do not change the pattern at all. You simply choose the right size by matching the stitch count in the pattern to the gauge you get with your yarn. The instructions stay exactly the same.

I’ll use the First Star sweater as an example, but this method works for any top down sweater or top.
(I personally design and knit only top down garments because this construction lets me check the fit of the yoke and sleeves early on, without having to knit the entire body first.)

Here is how:

• Pick the finished sweater measurement you want.
  This is usually the bust or chest measurement from the size chart.
• Find the body stitch count in the pattern.
  Go to the Body section and look for the stitch count right after dividing for sleeves and body. This is the point where the pattern usually says something like “work until the body measures …”.
• Check your gauge.
  Count how many stitches you get in 10 cm or 4 inches with your yarn.
• Match the numbers.
  Use your gauge to see which pattern size has a body stitch count that will give you the finished measurement you want. That size is the one you should follow, even if it is several sizes larger than your usual size.

Let’s walk through it with real numbers
Imagine you chose size Medium in the pattern. The finished sweater circumference in the size chart is 99 cm/ 39 inches.

The pattern gauge is 16 stitches in 10 cm/ 4 inches. This number is very important, because all sizes in the pattern are built on it.

Now we calculate the width of one stitch in the pattern gauge.

10 cm ÷ 16 stitches = 0.62 cm per stitch
or 4 inches ÷ 16 stitches = 0.24 inches per stitch

This means that one stitch in this pattern covers about 0.62 cm/ 0.24 inches of width.

 

Step 1. Find the Body stitch count for size Medium

Go to the Body section in the knitting pattern. Look for the stitch count right after dividing for sleeves and body. This number usually stays the same until you reach the bottom ribbing, if the pattern does not include waist shaping.

For size Medium, the pattern has 160 stitches at this point.

Now let’s quickly check the math:

160 stitches × 0.62 cm ≈ 99 cm
or
160 stitches × 0.24 inches ≈ 39 inches

This matches the finished measurement in the size chart, so we know the pattern numbers are correct.

Step 2. Now use your own yarn’s gauge
Knit a swatch with your yarn using the needle size recommended on the yarn label.
Let’s say your DK yarn gives you 20 stitches in 10 cm/ 4 inches

Now find the width of one stitch:

10 cm ÷ 20 stitches = 0.5 cm per stitch
or
4 inches ÷ 20 stitches = 0.2 inches per stitch

This means one stitch with your yarn is narrower than one stitch in the pattern gauge. In simple words, you need more stitches to cover the same width than the yarn used in the pattern.

 

Step 3. Find how many stitches you need 
Take the finished sweater circumference from the size chart, 99 cm or 39 inches, and divide it by the width of one stitch from your gauge.

99 cm ÷ 0.5 cm = 198 stitches
or
39 inches ÷ 0.2 inches = 195 stitches (let’s round to 198 stitches)

With your yarn, you need about 198 stitches in the body to reach a 99 cm or 39 inches circumference.

 

Step 4. Find which size in the pattern has about 198 stitches

Check the stitch counts for all sizes in the Body section. In our example:
• Size 2XL has 192 stitches for the body
• Size 3XL has 202 stitches

Both numbers are very close to the 198 stitches you need.

This means you can safely follow the written instructions for size 2XL or size 3XL, and with your thinner yarn, the finished sweater will fit like a size Medium.

You can already see the main limitation of this method. Larger sizes are limited by how the pattern was graded. Quite simply, the pattern may not include a size with a high enough stitch count to match your calculation.

If that happens, I recommend repeating the same math with a slightly thicker yarn. A good next step is a worsted weight yarn with a gauge of about 18 stitches in 10 cm or 4 inches, which often fits much more easily into the existing size range of the pattern.

What about row gauge?

We should not forget about row gauge. When you use thinner yarn, you may get a different number of rows per centimeter or inch. This means your garment can fit perfectly around the bust, but the yoke, body, or sleeves may end up a bit shorter than expected.

The good news is that most parts are easy to adjust.

• The body is the simplest one. You just knit until you reach the length you like.
• Sleeves can also be adjusted with a bit of a math, which I shared in this Esenote.
• The yoke needs a little more attention:

In raglan garments like the Mellow Mood Sweater, Mellow Mood Top, or Weekend Glow Sweater, the solution is often quite simple. If you reach the end of the yoke and feel that it is still a few centimeters or inches too short, you can continue knitting without any increases for a few more rounds.

The stitch count stays the same, the pattern still works, and the yoke becomes longer. This small adjustment is usually enough to fix row gauge differences in raglan garments.

❗️That said, I do not recommend changing the yarn weight in a pattern if you are a beginner. It is absolutely possible, as you can see, but it means you need to observe the fabric, check measurements, and be ready to adjust as you go.

If you enjoy a bit of experimenting, go for it. If not, choosing a yarn with the same weight and length as the pattern was written for will always be the safest option.

💡 I also would like to show you that this idea can work the other way around. In this project, Elaine needed a much smaller fit than the Weekend Glow sweater pattern offered, so she used thinner yarn and smaller needles.

The pattern gauge was 21 stitches, but her gauge was 24 stitches.
She followed the pattern exactly as written for the first size in the pattern, without changing any stitch counts. Because her stitches were narrower, the finished sweater came out smaller as well.

This is the same logic, just used in reverse.
More stitches per centimeter means a smaller garment. Fewer stitches per centimeter means a larger one.

It is a great example of how understanding gauge gives you more freedom, even when you stick strictly to the pattern instructions.

❤️ I hope this Esenote was useful and inspiring.

Warm regards,

Julia Piro

Knitwear Designer & Esenotes Curator

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