The fraction 22/722/722/7 as an approximation to π\pi π is most strongly associated with the ancient Greek mathematician Archimedes of Syracuse (around 250 BCE), not “discovered” by a single person in the modern sense.

Quick Scoop: Who “discovered” 22/7?

  • Archimedes is the first person we know of who proved that π\pi π lies between 223/71223/71223/71 and 22/722/722/7, i.e. 223/71<π<22/7223/71<\pi <22/7223/71<π<22/7.
  • Because of this, the approximation 22/722/722/7 is often called Archimedes’ constant and he is usually credited with popularizing it.
  • Historians are careful: people before Archimedes may have used numbers close to π\pi π, but no earlier proof involving 22/722/722/7 is known, so the credit traditionally goes to him.

What Archimedes actually did

Archimedes didn’t just guess 22/722/722/7; he used a geometric method with polygons:

  1. He inscribed and circumscribed regular polygons in a circle and kept doubling the number of sides up to a 96‑gon.
  1. From the perimeters of these polygons, he showed the circle’s circumference–diameter ratio must be between 223/71223/71223/71 and 22/722/722/7.
  1. That upper bound 22/722/722/7 turned out to be a very handy rational approximation and spread widely.

So, when people ask “who discovered pi 22/7” , the historically grounded answer is:

Archimedes of Syracuse is credited with discovering and proving the famous approximation π≈22/7\pi \approx 22/7π≈22/7, even though π\pi π itself was known and used long before him.

Information gathered from public forums or data available on the internet and portrayed here.