National Bikini Day in the United States Date in the current year: July 5, 2024

A bikini is a type of two-piece swimsuit consisting of two triangles of fabric on top and two triangles of fabric on the bottom. The top half of a bikini covers the breasts, and the bottom half covers the pelvis, leaving the navel exposed, and may cover the buttocks, although some bottom designs, like thong or g-string, leave the buttocks exposed.

Two-piece swimsuits have a long history. They are believed to have originated during the classical era, but those early two-piece suits were worn by women during exercising and playing sports. There is no evidence that they were used for swimming because back then, it was common to swim naked.

The first present-day two-piece swimsuit was introduced by American designer Carl Jantzen in 1913. It consisted of shorts and a short-sleeved top. Two-piece swimsuits became common in the 1920s, but they were much less revealing than they are now. Midriff exposure gradually became more acceptable throughout the 1930s and 1940s, but the real swimwear revolution took place after World War II thanks to the invention of the bikini.

As people were looking forward to enjoying their first war-free summer in years, French designers were searching for ideas of swimwear that would match the people’s uplifted spirit. It was somewhat difficult due to a fabric shortage, but two designers, Jacque Heim and Louis Réard, figured out how to make lemonade out of lemons that life had given them.

Heim was the first to introduce a revealing swimsuit design in January 1946. He called it the atome. Although Heim marketed the new model as the “world’s smallest bathing suit”, it still covered the navel.

Heim’s main competitor Réard revealed an alternative two-piece swimsuit design on July 5, 1946. He named it the bikini after Bikini Atoll in the Marshall Islands, where the United States had conducted the first of many nuclear weapon tests mere days before Réard’s presentation of the swimsuit.

Réard’s design was even more revealing than Heim’s. It consisted of two triangular pieces of fabric that covered the breasts forming a bra, and two triangle of fabric that covered the pubic mound and the buttocks connected by a string. The bikini was widely covered by the press, but it took the general public some time to accept the revealing garment. Bikinis didn’t become truly popular until the 1960s.

It is unknown who came up with the idea of celebrating National Bikini Day and when it was celebrated for the first time, but the holiday is quite popular despite its unofficial status. To celebrate National Bikini Day, put on your best bikini and go to the nearest beach or pool to swim and sunbathe. It is also the perfect occasion to go shopping for a new bikini. And don’t forget to share your photos in a bikini on social media with the hashtag #NationalBikiniDay to promote the holiday.