Grade up or down a size or two2

How to Grade a Pattern Up or Down a Size (or Two)

Have you fallen in love with a pattern, only to find that it doesn’t come in your size? A few ladies told me that Itch to Stitch’s patterns don’t come in their sizes – some are smaller and some are larger than the measurements. Perhaps you have a tween who is not quite big enough to wear adult sizes, but too big for kid’s patterns. Perhaps you have a paper sewing pattern whose size range is just outside of yours (paper patterns come with one size range in an envelop, e.g., 6-8-10-12-14 in one envelop and 14-16-18-20-22 in another).

There’s no need to despair. With a little time and some effort, you could grade the pattern up or down.

This method is a pretty safe bet to change up to two sizes.

The caveat is that the pattern must be evenly graded.

Evenly Graded?

What does “evenly graded” mean? It means at any specific point (let’s say, the waist), the measurements between sizes are the same.

Here’s an example (hypothetical numbers):

Size 00 Size 0 Size 2 Size 4 Size 6
Waist 64 cm 66 cm 68 cm 70 cm 72 cm

You see that each waist measurement is 2 cm larger than the previous size.

However, it doesn’t mean that every point on the pattern must increase by the same amount. In fact, it’s likely that it doesn’t grow by that same absolute amount. Think about when a person gains or loses weight, some part of her body would increase/decrease more than others. And no matter how much weight she gains or loses, she wouldn’t be taller or shorter.

Here’s the example:

Size 00 Size 0 Size 2 Size 4 Size 6
Waist 64 cm 66 cm 68 cm 70 cm 72 cm
Neck to Waist Length 35 cm 35.25 cm 35.5 cm 35.75 cm 36 cm

In the example, while the waist still grows 2 cm per size, the neck to waist length only grows by 0.25 cm per size.

This is typical of women’s patterns. The “big guys,” such as Burda, Vogue, McCall, Butterick and Simplicity, all have evenly graded patterns. The indie pattern companies, such as Jalie and Silhouette also evenly grade their patterns, although some patterns have huge size ranges, so they may evenly grade only within a sub-range. For example, misses 8 to 16 are evenly graded, and women’s 18 to 24 are evenly graded. As long as there are three or more sizes graded evenly in a pattern, you can still deploy this method.

You don’t have to study very hard to discover whether a pattern is evenly graded. You can pretty much recognize it at the first glance. (This is the Vienna Tank.)

Evenly Graded

Evenly graded.

Some of Itch to Stitch’s patterns are not completely evenly graded across all the sizes. For example, in Lisbon Cardigan, the larger sizes have increasingly longer bodice, whereas the smaller sizes have the same bodice length. However, because there are more than 3 sizes in one range, you could still use this method to grade up or down.

So maybe this is an unnecessarily long-winded explanation. Most of the time, you can use this method anyway.

Let’s get started.

How to Grade

(Click to see larger images.)

Step 1: Determine how many sizes you need to go up or down.

This is body measurement table for most of Itch to Stitch’s patterns.

How to grade a size up or down

Notice that for each size, the bust is increased by 1 3/8″ (3.5 cm), the waist by 1 3/8″ (3.5 cm) and the hip by 1 3/8″ (3.5 cm). These figures happen to be the same, but they don’t necessary have to for other patterns.

So if there are two sizes bigger and two sizes smaller, the measurements would look like these:

Screen Shot 2016-07-07 at 10.47.00 AM

Are you grading one size smaller/larger? Or two sizes?

Step 2: On the pattern, draw a straight, guiding line to connect the “corner points”.

How to grade a size up or down


How to grade a size up or down

Step 3: Measure the amount between sizes along each line. If you don’t have too strong of an aversion to the metric system, I think it’s easier to use millimeter (smaller unit is easier). But either way would work. I am going to use millimeter here.

How to grade a size up or down

Step 4: Plot the next size (or next two sizes) using the measurements.

How to grade a size up or down

The same logic applies with grading down.

How to grade a size up or down


Step 5: Repeat step 2, 3 and 4 along curves. More plots along the curves make it easier for you to connect them smoothly and accurately. There is no absolute number of lines that you need to follow. You can do it sparingly but enough to make you comfortable with drawing the curve. Try to have the straight guiding lines perpendicular (the right word is probably “tangent”) to the pattern lines but you don’t have to be insanely precise (we are increasing/decreasing one or two sizes). You don’t need to draw more straight guiding lines along the straight part of the pattern lines; those are easy to connect.

In the following example, I am going to continue on increasing one size only, but you get the drill of increasing two sizes or decreasing a size or two.


Grade up or down a size or two2

Step 6: Connect the dots as smoothly as you can.

Grade up or down a size or two2


After you draw all the dots and connect all of them, it will look like this:

How to grade a size up or down

Repeat for each pattern piece and there you go!

I hope this is helpful. Keep stitching!