There's actually a rule
Why are buttons on men’s and women’s shirts always on opposite sides?
The placement of buttons on men's shirts on the right and on women's shirts on the left originates from social and cultural habits that have existed for centuries. Understanding the reasons behind this arrangement gives us insight into the context of fashion in the past and explains the continuation of this tradition in modern fashion.
When buttons were invented in the 13th century, they were very expensive, and only upper-class women had the opportunity to wear clothes with buttons. The placement of buttons on the right for men and on the left for women was not only related to the practicality of design but also reflected the gender and class distinctions in society.
In the 13th century, common women used fabric ties or wooden clasps to fasten their claothes, while middle and upper-class women often wore elaborate outfits fastened with expensive buttons made of gold, silver, pearls, gemstones, and ivory — a trend that laid the foundation for the future distinction between haute couture and everyday fashion.
At that time, wealthy women wore clothes with buttons, but they didn’t dress themselves; their maids did it for them. Since most people were right-handed, the buttons had to be on the left to make it easier for the person standing opposite to fasten them. The placement of buttons on the left for women’s clothing was a subtle indication that the family was wealthy, a characteristic of the upper class.
For men, the placement of buttons on the right may have originated from the military. Most men are right-handed, and placing the buttons on the right made it easier for them to access weapons hidden inside their clothing. In the past, when men took on roles in hunting, the movement of drawing weapons typically went from left to right, so the fastening of buttons and clasps on clothing was designed on the right to suit this body movement.
Today, times have changed, but men’s clothing still retains many features of old military uniforms. The habit of fastening and unfastening buttons with the left hand became common for men over thousands of years of warfare. The tradition of button placement continues and has become a fashion standard, though not a requirement. This represents both stability and a connection to the past, as well as a reflection of style and aesthetics in modern fashion. This is why buttons on men’s and women’s shirts are always on opposite sides.
