Ever felt like your dress shirt was giving you wings like a flying squirrel? That my friend is whats called the dress shirt batwing. It's that stupid excess fabric that hangs around under your armpit, making it look like you could go paragliding if you wanted too. So damn ugly.

And it’s not just about looks—batwing can make wearing a dress shirt that you really like super uncomfortable. Nothing better than finding a banger of a dress shirt with a great pattern or color only to absolutely hate wearing it.

You might think, "Okay, let's just DIY tailor it by taking in the side seams and sleeves a bit, that should fix it". And while that sounds like it makes sense and will solve your problem, trust me, batwings are stubborn and don’t always go away that easily.

But don’t worry, I've got a method that’ll help you clip those stupid ass batwings for good.

Now, before we get too far into this, let me clear something up real quick. This might seem like a complex math lesson but don’t panic, it isn’t at all. I mean, my geometry knowledge is literally stuck at a 7th grade level. So we’re definitely keeping it simple here. But, yes, a little bit of geometry and a basic understanding of human anatomy come into play.

I did struggle helping my daughter with her 4th grade math so maybe 7th grade is pushing it for my knowledge…

Getting (SLIGHTLY) Technical

When you’re about to tailor your shirt, measuring and pinning the side seams is usually where you start right? But here’s the thing: getting those measurements spot-on doesn’t always solve the batwing dilemma.

I learned this the hard way. Back in the day, I would just run a straight stitch up from point A to point B without thinking about the angle underneath my armpit very much at all. I’d hope for the best, and more often than not, I ended up with something that felt like sandpaper under my arm.

Super frustrating.

The Anatomy of a Good Fit

Let’s switch gears and talk a bit about anatomy, Dr. House style—without the grumpiness and pain pill addiction. We’re dealing with your shoulder joint here, which is a fancy ball and socket joint that allows for a whole 360° motion. It’s pretty smooth and efficient right?

This is what lets you reach for those hidden Oreos on the top shelf away from your kids, or allows you to bend over and tie your shoes without ripping your shirt Hulk Hogan style.

Your shoulder joint is also relatively high on your arm. However, most off-the-rack dress shirts have armholes that are way too low. It’s a mystery to me why they do this because it just restricts your movement and just plain looks stupid. You want to move those armholes higher to keep everything comfortable and functional (but we’ll get there).

A Little Geometry Surprisingly Goes a Long Way

Here’s where a bit of geometry comes into play. If you’re tailoring the arms in addition to the body of your dress shirt, try to connect your side seam and your arm seam at about a 50° angle. I know, I know, you didn’t expect to get geometric angles in your DIY tailoring tutorial. But this angle typically aligns well with the natural angle of your armpit, allowing the fabric to lie comfortably under your arm without causing any annoying rubbing or chafing.

Ask me how I know.

And how precise do you need to be with that 50° angle? It’s absolutely life or death. If you don’t hit that angle exactly you’re going to completely ruin your dress shirt.

It’s not that serious. A little wiggle room is all good in the hood—think 48 to 52 degrees.

Remember, DIY tailoring isn’t about making our clothes look perfect. It’s more about customizing our clothes to fit the way you want, and making them comfortable while being flattering at the same time. Not a word guys use very often I know, but it’s the best one to use here.

There aren’t any hard and fast rules that you have to follow by any means. Actually that’s not true, the only rule I have is you need to start.

You Got This!

That’s it dude! A pretty easy and fix to one of the most commonly frustrating issues with tailoring your own dress shirts. No more stupid ugly batwings, just a smoother, more comfortable fit that looks as good as it feels.

And the best part? You don’t need to be a geometry ace or an anatomy expert to make it happen. I mean…4th graders can do it.