Introduction

One of the biggest mistakes a beginner sewist can make when sewing clothes is picking the wrong size to sew. While it could appear to be straightforward – Sew the size you wear.

Right, but what size do you really wear? Let’s take a look at choosing the correct pattern size for sewing clothes using your body measurements.

Pattern Size vs Ready-to-Wear Sizing

When you shop at a store for clothes, you are shopping for “ready-to-wear” clothes (unless you are going somewhere to get a tailored suit or custom gown, etc). It’s important to remember that ready-to-wear sizing is made up by the garment manufacturers. Each brand will have its own sizing block and size scale. So, it’s frustrating enough that a size 14 from one brand might fit, but a size 14 from another wouldn’t fit at all. Or, it might fit ok in the hips but be too tight in the waist or something.

That’s because there is no standard sizing out there. Each company decides it’s sizing based on it’s target market.

Patterns are similar.

However, when you are picking your pattern size, you need to be armed with your body measurements and the back of the pattern envelope (in some cases, the size chart might be on the front or the flap, but it will be on the outside of the pattern).

Do not assume that the size you wear in ready-to-wear is what you will sew from a pattern. Over time, I think ready-to-wear sizes have changed so that what once was a size 12 is now a size 8. Of course, that depends on the garment designer.

But pattern sizing has stayed pretty consistent over the decades. This means that if you generally wear a size 8 in ready-to-wear, you might need to sew a size 12 or 14 to get the correct fit.

It all depends on your measurements, though.

Don’t despair, size is just a number. Sewing your own clothes means you can get a great fit because you can customize the pattern to your specific measurements.

Essential Body Measurements Needed for Choosing the Correct Pattern Size for Sewing Clothes

There are generally 3 measurements needed to pick a pattern size. Or rather, in general, pattern companies put size charts on their envelope that show 3 measurements.

Those three measurements are Bust (or chest), Waist, and Hips. On rare occasions, you might see a torso or a girth measurement typically for swimsuits, bodysuits, or leotards.

It’s important to take your measurements accurately. Remember, you are doing this so you can sew well-fitting clothes. And if you try to inflate or deflate your measurements, your fit will suffer.

That being said, these are the 3 measurements you need to have to pick your pattern size for MOST garments. However, there are a lot more measurements you will want for altering your patterns.

How to Use Size Charts on Patterns

The first thing to note is that a pattern will usually have Bust, Waist, and Hips measurements listed in columns by size. So on the left of the chart, you’ll see the label for each row, and then across the top, you’ll see the size assignment for that column.

As I said before, don’t get hung up on the size label. I’ve even seen patterns that use letters, which, in my opinion, is nice because there is no direct comparison to what we think we should be wearing from our ready-to-wear closet.

Some patterns still only include a few sizes in the envelope, so make sure to buy the correct set of sizes. And if you are between two sizes that span two different envelopes, you may need to buy both, depending on the garment or garments in the pattern.

That being said, you don’t actually need all three measurements for every type of garment. So, let’s dive a little deeper into choosing the correct pattern size for sewing clothes based on what you plan to sew.

Tops

You will generally use the bust or chest measurement to decide what your pattern size is for sewing a shirt, blouse or top.

Side Note: I’m calling out bust and chest measurements because pattern companies will list “Bust” on “female” type patterns and “Chest” on “male” type patterns. They aren’t exactly the same measurement technically, but they are similar enough that I’m classifying them the same but I’m still calling them out separately because of the nomenclature on patterns.

In general, the widest part of your torso above your hips, not including your shoulders, is your bust/chest area. This could simply be because you are a weight lifter and have massive lats. But it could also be due to large breasts. Or, just because you’re a typical human. So, you want to pick your shirt size based on your chest or bust size (primarily).

One of the most difficult areas of the upper torso to modify fit is the shoulder. So, getting the shoulder right initially is important because most tops will hang off the shoulder (not all, I know that, but most do). But they don’t use a shoulder measurement to size patterns. So, the next best thing is going to be the bust/chest measurement. Also, you don’t want your button-downs to gape or be too tight in the chest. Typically.

So, what do you do if your waist size is much bigger than the waist measurement of the pattern size that coincides with your bust/chest?

You alter the pattern. OR. You pick both, and copy both sizes onto paper and blend the larger waist size into the smaller bust/chest size.

And honestly, you’d want to do this if your waist measurement is much smaller than the waist measurement that corresponds with your bust/chest pattern size.

What if your bust/chest measurement is between two pattern sizes?

If you tend to be petite-framed (narrow shoulders), you can try the smaller size.

But in general I’d suggest trying the larger of the two sizes. A slightly larger size shirt will be wearable, but a too-small one might not be.

Ideally, you’d pick one and make a muslin – a test garment out of similar fabric – to see how it fits. Then make your decision based on that.

If you are a person with breasts, and you are making a pattern drafted for “females” keep in mind that the drafted cup size is typically a “B” cup, unless otherwise stated. So, there will likely need to be alterations in this area to get a really good fit. Some tops won’t matter much, but some styles benefit greatly from fit adjustments in the bust area. Especially for a “full bust”.

So, if you have a very narrow back, and a very large cup, the smaller sized pattern with a full-bust adjustment might fit you better overall.

Bottoms

For bottoms, the widest part of your torso below your waist is your hips. So, keeping with the “fit the widest part” theory, you should pick your pattern size according to your hip size.

For bottoms, there are two types of bottoms, skirts and trousers or pants (for you non-British folk 😉).

For either to fit good, the waist-to-hip ratio needs to be correct. But it’s going to be easier to make fit adjustments in the waist if the hip fits, than to make fit adjustments in the hip. Especially with pants (trousers).

As with the tops, if you are two different sizes according to your measurements, you can use both sizes and blend between the two. Use the hip size as your main size for below hip and blend into the waist with the new waist size.

Or, you can do fit adjustments utilizing darts or even side-seams.

So what if your hip measurement falls between 2 pattern sizes?

Again, I typically say go with the larger of the two. The same philosophy applies. You can still wear a garment if it’s a little too big, but if it’s a little too small, you probably can’t. Sew a test garment. Nothing will tell you how well something fits as much as a test garment will.

Both (Dresses or Jumpsuits)

So, how do you pick a size if you want to make a garment that has a top and bottom connected?

Well, that’s going to be more tricky if you don’t fall in line with the listed measurements.

You could choose the larger of the two sizes that corresponds with your hip or bust/chest measurement.

You can also take into account the style of the garment that you are making.

If you are making a dress that has a flared skirt, hip size won’t matter nearly as much. So just go with the bust size.

If you are making bib-overalls, bust/chest size won’t matter, so go with hip size.

But if you do need to take into account both, like for a jumper, romper, or slim-fit dress, then probably pick bust, and adjust the rest. If you have to use one size for the top and blend into a different size for the bottom, that works too.

And again, if you are between sizes with your measurements, I typically say go with the larger one. But do a test garment. That will also tell you if you need to make additional alterations for fit.

Basic Pattern Adjustments

Most patterns will come with some bare-bone “Lengthen or Shorten” here marks on them. You’ll see this for sleeves, pant legs, skirts or dress bottoms, and sometimes shirts.

These adjustments should be made in accordance to your physical measurements.

And obviously, bust/chest, waist, and hip measurements are not going to tell you how long a pant leg or sleeve should be. You’ll need additional measurements.

I have a very large list of measurements with reasons you might want to take each (buying clothes, sewing clothes, pattern drafting), and detailed instructions on how to take each measurment. Plus printable sheets you can store in a binder for future reference.

Three other common fit adjustments that might be needed are: Shoulder slope, bust (for full or less full busts than B cup), and the crotch curve.

Each of these adjustments, when done well, will result in a MUCH better fitting garment. But they are more complicated than just lengthening or shortening a sleeve. And often they affect some other parts of the pattern as well. So, take your time and do some research before making a lot of modifications.

And save yourself a bit of a headache, and trace your patterns onto other paper to save the original in case you need to go back to it.

Two more thoughts on pattern sizes and measurements.

One: Pattern sizes are not guaranteed to be the same across all patterns. Even within the same brand, there may be different pattern designers who use different measurement blocks and grading scales.

Two: Check your own measurements every 6 to 12 months to make sure.

Conclusion

Pattern sizing is not the same as ready-to-wear sizing. To get the best fit, choose the pattern size based on your own measurements.

Keep track of your measurements in a notebook or somewhere so you don’t have to constantly remeasure yourself.

If you need ot make fit adjustments, you’ll need more measurements than just the ones listed on the back of the envelope.

Check out my downloadable measurement sheets with illustrations and how-to measure instructions.