You’ve probably heard that your fit model should be a size medium (or whatever size is in the middle of your size range). You might be wondering what size medium actually means for your brand and for the body measurements of your fit model. When you are developing a new brand or product category from scratch, you want to make your brand’s sizing something that makes sense for your target customer.
There is no universal standard for what a size medium (or any other size) should be. However, there are size standards and research that can guide you. ASTM sizing and Alvanon’s sizing standards are places I recommend for good base measurements. I use both the ASTM missy and women’s standards and Alvanon’s north american women’s and plus women’s standards in my work and find them to be pretty representative of the average woman in the US.
The next step of determining your brand’s size medium is to consider your target customer. She may have a specific body type, height, or age that warrants tweaks to the sizing standards you started from. Alvanon does have standards for niche fits like petite, tall, curvy, and athletic that you can explore and use when needed. If you have sizing and fit data from your customer research, you can use that to adjust your brand’s sizing to fit your brand’s specific demographic.
Another way to reference and set your brand’s medium is to compare the size charts of other brands your target customer shops at. You can technically call your medium whatever size you want, but it is helpful to have your sizes somewhat in line with other brands in your customers’ closets. This way they will easily know what size to order in your brand. Take a look at the size charts on the websites of comparable brands of a similar price point to yours. What body measurements do they call their medium?
If you aren’t as good with all the numbers, but know several people who represent your ideal customer, you can always get their measurements and ask what size they usually wear. This can help you visualize your sizing by comparing the sizing you’ve drafted for your brand to actual people.
Determining what your brand’s size medium actually is usually calls for a combination of these methods as well as conversations with your patternmaker and other experts on your team.