Are Shirt Sizes Universal?

Men's clothes on hangers by size
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Imagine yourself finally receiving this nice dress shirt you’d want to wear for a weekend trip. As you try it on though, you realize something – it’s fitting you like a compression shirt.

As someone who’s always toeing the line between large and extra-large, I get you. I’ve said “but I’m a large at the other store” a couple of times before, too!

This size debacle might make you question the whole thing – are shirt sizes universal?

Believe me when I say that it’s a resounding no. Although there have been sizing standards published by different organizations, they have never been mandatory. At the end of the day, manufacturers still have the last say on how large their large is.

We have gathered information on the whys of the size differences, and on how shirt sizes work. Of course, we also have steps you can take to never fall for this tight trap again.

Why are clothing sizes so different?

A brand’s clothing size all boils down to the manufacturer’s discretion. Different factors come into play on how and why they come up with their sizes.

Lack of a Mandatory Sizing Standard 

The International Organization for Standardization, or ISO, has been publishing standards for clothes sizing as early as 1977. Currently, their standard ISO 8559, made in 1989 and updated as recently as 2018, is their reigning standard for clothes sizing. 

I can already hear you – “why isn’t this being followed, then?”

Well, it’s just a standard at the end of the day. It’s not really mandatory to follow their guidelines or any of the standards made by individual countries.

Yes, you heard that right. There are also sizing standards made by different countries separate from the ISO standard. Sizing standards are also made by the United States, Japan, and China.

And yes, they are not mandatory as well.

Size Differences Across Countries

Historically, Asian people have always been smaller than their American counterparts. This is reflected in the clothes marketed towards people that live in these different countries, in that America’s large shirt is larger than Asia’s.

This is not to say that big guys do not exist in Asia and that there are no small people in the West. It’s just that the average Asian is smaller than the average American.

You’ve probably noticed that Asian countries, such as Japan and China both made sizing standards for their own countries. I’m not saying that this is because of the differences in the average bodies between countries, but it kind of implies that, does it not?

There are other examples of this, of course. Another example is that Australian shirts are often said to run bigger than the ones from the UK.

Manufacturer’s Target Market

Manufacturers adjust the size of their clothing for their target market, too.

This one is more noticeable when we compare the extremes – you can’t compare a large toddler shirt to a large shirt you own!

If a brand is catering to teens, then you can expect that their sizes run smaller. On the other hand, if a brand is one that’s built for dads, then most likely their sizes run bigger. Even if just by a tad.

This factor is a bit connected to the factor above. If the size of your target market’s bodies is smaller on average, of course, you’ll adjust your measurements to cater to them more.

Vanity Sizing

Wait, what is vanity sizing, anyway?

This phenomenon is observed when a brand intentionally changes the size of its garments to give its customers the illusion of wearing a size smaller than usual. 

Vanity sizing is usually done because of different reasons. Maybe they want to cater to the rising rates of obesity. Or they want to cater to their target demographic more. 

Lastly, maybe brands simply just want to flatter their customers by saying they’re smaller than they think they are.

You might ask, with those given reasons and others that only the manufacturers know of, is vanity sizing real?

Honestly, who knows? Nobody would come up and say they practice vanity sizing. Even if studies can document that some brands run bigger than others, manufacturers can just sweep this under the rug by stating some other reason.

There’s nothing wrong with vanity sizing at the end of the day. In fact, I get the charm of it. Do I want to wear a medium shirt again without putting any effort into my diet or exercise? Sign me up!

However, the problem lies when the customers do not know when a brand practices this and they don’t get the chance to fit the garment. 

The Opposite of Vanity Sizing

On the other hand, some brands are notorious for having sizes that run smaller. 

One can argue though that their target consumers are those that are skinny, hence the smaller sizes. 

The fact remains, however, that this practice is being done by brands. So yes, prior research before buying clothes is important especially when returns are kind of complicated.

And no, we won’t drop names!

How do I know my shirt size?

Look, you can always just order away and throw caution in the wind. If it fits you, great. If it doesn’t, well there’s always room for exchange, refunds, or even regifting!

At the end of the day though, it’s still better to know your shirt size. Exchange or refunds can be quite the hassle, and who knows if your younger brother would like another gray shirt on top of his ever-growing collection of shirts in grayscale?

The first thing you can do is to fit it first before buying it, of course! By trying it on, you’ll have an idea if that shirt fits you perfectly. 

This is not to mention that you might also get some realizations while fitting the clothes. From colors that look better on your skin to the way the collars are cut, some details can only be seen when you’re already wearing the garment.

So yes. Fit it if you can.

In cases where you can’t fit them though, you can always measure the proportions of a shirt that fits you really well and compare it to the size chart of the brand.

You can also go to the extremes here and measure your features! This is easier to do though when you’re with somebody else who’ll be taking the measurements, and hopefully, they know what they’re doing. 

Better if they’re a tailor. 

Even though most brands go by the alpha sizing, or through the standard small, medium, and large, their size charts still have conversions of these sizes either through inches or centimeters. 

Just line up your measurements with its equivalent in their sizing, and you’ll be good to go.

As long as you can measure your shirt or your body correctly, you should wind up with a shirt that fits you properly.

There are also apps and online services now where your body is scanned and that will give the website your proportions, which you can then use as a guide for buying shirts. 

I can’t personally attest to their accuracy as I haven’t tried using one, but it’s just so amazing how far technology has come today! 

Who knows, maybe one day somebody can come up with a way to standardize the shirt sizes once and for all. That’d be a killer project, I think!

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