National Twins Day

Two adorable identical children dressed in matching outfits, holding hands and smiling in a sunny park..
National twins day illustration

Ever looked at your reflection in the mirror and thought, 'One of me is fun, but two would just be double the trouble!' Well, on National Twins Day, you can celebrate exactly that, just without the mirror trickery! Originating on the magical internet, National Twins Day has seen its popularity double, triple, and, predictably, twin in the years since its digital birth.

When is Twins Day?

It's national twins day on the 3rd August.

The History of National Twins Day

Not to be confused with its offline sibling, the Twins Days Festival in Ohio, National Twins Day emerged online like the surprise revelation that you have an identical twin! Accurately pegging the exact date of this online phenomenon isn't easy, but, lo and behold, the magnifying glasses of the internet detectives are hard-pressed to let us down. According to them, the suspicious activity of twin mentions began to hit the internet around 2018.

The 'Twin Peaks' in Online Mentions

The popularity of National Twins Day online saw its zenith on August 3, 2018, with a whopping 2594 mentions in a single day! Some may speculate this to be the work of mirror witchcraft, but we say it's just the magic of the internet and twins!

Twins: Double the Fun!

Here's the thing about twins - they come in pairs, they become bff's by default, and they’ve got the unique privilege of celebrating their bond on a dedicated day. So, if you, your loved ones, or your friends are of the twinning kind, then National Twins Day is just the day to double the celebration!

Join The Celebration

How, you may ask? It's easy! By posting your twinny photos, sharing heartwarming tales of twin mischief, or even dedicating a sweet nothings post to your twin on social media, you’re contributing to those grand numbers and giving the true meaning to 'Seeing Double'.

History behind the term 'Twins'


First recorded usage

The term 'twins' was first recorded in 1664, derived from the Old English word 'twinn', meaning 'double'. It was used to refer to two individuals born from the same pregnancy who share a close bond due to their simultaneous arrival into the world.


Scientific recognition

In 1819, the term 'twins' gained recognition in the scientific community thanks to the work of the German physician and anatomist, Johann Friedrich Blumenbach. Blumenbach studied various aspects of twins and classified them into different types based on their development and genetic makeup.


Identical vs. fraternal twins

The distinction between identical and fraternal twins was first established in 1932 by the American geneticist, Horatio Newman. He discovered that identical twins result from the fertilization of a single egg, splitting into two embryos, while fraternal twins develop from the fertilization of two separate eggs by two different sperm.


Twin studies and genetics

In the 1970s, twin studies gained significant attention, particularly in the field of genetics. Researchers utilized twins to examine the influence of genetics and environment on various traits and diseases, ultimately leading to valuable insights in areas such as hereditary diseases, behavioral genetics, and the nature versus nurture debate.


International Day of Twins

The International Day of Twins, celebrated on August 3rd each year, was established in 1997 to honor the uniqueness of twins and promote awareness about twin-related issues. This day celebrates the special bond between twins and recognizes their significant contributions to society in various fields.

Did you know?

Did you know there's an actual name for the phenomena of self-image reflection called 'autoscopic phenomena'? That's right, folks! We all have a bit of a 'twin' inside us...quite literally, if you consider our reflections!


fun loved ones rememberance celebration twins

First identified

7th August 2015

Most mentioned on

3rd August 2018

Total mentions


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