How to Choose a Size in a Knitting Pattern

Knitting yourself a garment that you love to wear is incredibly rewarding, at the same time, if you are newer to knitting your own clothes you may struggle to get the result that you want. There is little more disappointing than spending A LOT of time and money on a project, only to discover your new piece doesn't fit you. So, how do you choose a size in a knitting pattern?

There are two skills that you need to develop in order to knit from a pattern successfully. The first is proper gauge, which I'll share more about in another blog post. The second is the ability to read a size chart and measure yourself properly.

How to Measure Yourself

If you are knitting a sweater, tank, tee, or dress the most important numbers to know are your full bust, upper bust and crossfront measurements. In the case of a dress you will also need to consider your hip measurement as well as your height to make sure the skirt of the garment also fits you as desired. As most handknit garments are sweaters or other tops, this post will focus on measuring yourself for a handknit sweater.

Full Bust

A tattooed woman measures around the fullest part of her bust.

Most people with breasts are familiar with their full bust measurement. Your full bust is exactly what it sounds like, the widest part of your bust. A lot of commercial size charts (like the ones you see when you shop for clothes online) will offer their sizes based entirely on full bust measurement.

Unfortunately, this is probably the worst measurement you can use to choose your size. Don't get me wrong, it is useful and important to know your full bust measurement. However, breast size varies enormously. Three women who are the same height and weight could have three completely different bust sizes. Additionally, three women with the same crossfront measurement can also have wildly different bust sizes. In short, your full bust measurement only tells you about the widest part of your chest and doesn't help predict your other measurements.

So if the most commonly used measurement isn't the best one to use, what measurements should you use instead? What measurement tells you how to choose a size in a knitting pattern?

Upper Bust

A tattooed woman in a purple leotard measures around her back, and then above her bust to mark her upper bust measurement.

Your Upper Bust measurement is a much better indicator of what size sweater or top will fit you best. As seen in the photo to the left, your upper bust measurement goes around your back where your full bust measurement does, then wraps up and across your chest over the very top of your breast tissue. Essentially, this is your chest measurement without your breasts.

When choosing a size based on your upper bust measurement, you compare the full bust measurement as listed in the garment with your upper bust measurement. For example, my own full bust measurement is about 36" and my upper bust measurement is about 32.5". When choosing a size, I use a bust measurement of 32.5" and the designer's recommended ease to choose a size. So if a sweater recommends 2" of positive ease, and the schematic offers a sizes with 30", 34", and 38" bust measurements, I should choose the 34" size.

In the example above, a 34" sweater will fit my upper bust with 2" of positive ease; however, it will also fit my full bust measurement with 2" of negative ease. This means that the fabric will be stretched across my full bust, which will result in the fabric in the front of the sweater being shortened, and the hem will lift in the front only.

In order to get the "best" fit in the example I'm offering, I would want to use a Full Bust Adjustment (aka bust darts) to offer the extra room I need in the bust and bring the front hem of the my top parallel to the floor. I put best in quotations because you may be perfectly happy with the fit of a garment without working a Full Bust Adjustment. There is nothing inherently wrong with a garment that lifts a bit at the front hem.

Choosing a size based on your upper bust measurement will help you make sure that the garment you knit will actually fit your shoulders. Imagine a top on a hanger, you are basically the hanger when you wear a top. Garments need to fit well across your shoulders in order to be comfortable and stay on your body. This leads us the final measurement we'll discuss, the crossfront.

Crossfront/Crossback

A tattooed woman measures her crossfront, between two invisible bra straps.

Your crossfront measurement is the span of your shoulders minus your arms. The easiest way to get this measurement is to measure from strap to strap when wearing a bra or fitted camisole. Your crossback is the same measurement on the back of your body, but it is unlikely you can measure your own crossback.

Comparing your crossfront measurement to the listed crossback measurement of your garment is another way to confirm your best fit. If you are making a set in sleeve garment, this measurement should be very close to your own with no positive ease. Positive ease in your crossfront measurement will result in more of a drop shoulder garment, the shoulders will sit on your arms rather than on your shoulders. 

When comparing your crossfront measurement, you will look for the "crossback" measurement in the schematic of your pattern. This is measurement of the sweater after the armholes have been shaped. In such a case where your UPPER bust and crossfront measurements place you in different sizes on a schematic, you may wish to make some modifications to ensure the best fit.

If you are knitting a set-in sleeve design, I would ultimately recommend you choose the size that best fits your crossfront.  This places the shoulder seams of your garment where you'd like them. For a raglan or drop shoulder construction, use your upper bust measurement to finalize your size. The shoulder placement on these designs is less crucial. 

In the end, there is no substitute for experience. I try to view each finished project as a huge success. If a finished sweater is a perfect fit it certainly feels great! When a finished sweater does not fit I hope to learn as much as possible from what went wrong. Then I hope to find someone who may fit the sweater better.

What's your experience with sizing? Do you use your upper bust or full bust measurement? Has this article helped you with how to choose a size in a knitting pattern? I'd love to hear from you in the comments!

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