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Celebrating π Since 1999 | The Ultimate Pi Resource

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π

Explore One Million Digits of Pi

Access, copy, and analyze π to its millionth decimal place

What is Pi (π)?

Pi (π) is the ratio of a circle's circumference to its diameter. It's an irrational and transcendental number that continues infinitely without repetition or pattern. In 2025, we continue to explore its mysteries and applications across mathematics, science, and technology.

First 100 Digits of π

3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067

Latest Pi Achievements (2025)

Computation Record

As of 2025, pi has been calculated to over 100 trillion digits using quantum computing technology, surpassing all previous records.

Memory Record

The human memorization record stands at 70,000 digits, achieved in 2024 after a 24-hour recitation.

AI Applications

Neural networks are now using pi-based algorithms for advanced pattern recognition and quantum error correction.

Pi in Modern Science

In 2025, pi continues to play a crucial role in:

Quantum Computing

Pi is fundamental in quantum error correction codes and quantum circuit optimization.

Space Exploration

NASA and private space companies use pi in calculating orbital mechanics for Mars missions.

Climate Modeling

Pi-based calculations help in creating accurate climate prediction models.

Artificial Intelligence

Neural network architectures utilize pi in optimization algorithms.

Want to discover more fascinating facts about Pi?

Explore All 101 Pi Facts →

Historical Timeline of Pi

1900
BCE

Ancient Babylonian Approximation

Babylonian mathematicians estimated π as 3.125 using the ratio of a hexagon's perimeter to the circumference of the circumscribed circle.

250
BCE

Archimedes' Method

Using a 96-sided polygon, Archimedes calculated π to be between 3.1408 and 3.1429, a remarkable achievement for ancient mathematics.

1400

Indian Mathematics

Madhava of Sangamagrama discovered infinite series for π, calculating it to 11 decimal places using his groundbreaking series.

1706

Symbol Introduction

William Jones introduced the π symbol, which was later popularized by Leonhard Euler, becoming the universal symbol we use today.

1882

Transcendental Proof

Ferdinand von Lindemann proved that π is transcendental, confirming the impossibility of squaring the circle with compass and straightedge.

1949

Computer Era Begins

ENIAC computer calculates π to 2,037 digits, marking the beginning of the computer age in mathematical calculations.

2024

Quantum Computing Record

Quantum computers achieve an unprecedented calculation of π to 100 trillion digits, setting a new world record.

Pi in Nature and Science

River Meanders

The ratio of a river's actual length to the distance from source to mouth approaches pi.

DNA Structure

The helical structure of DNA has a pi-based geometric relationship.

Wave Patterns

Ocean waves and sound waves follow pi-based mathematical patterns.

Quantum Mechanics

Pi appears in fundamental equations describing particle behavior.

Fun Facts About Pi

Never-ending

Pi has been calculated to over 100 trillion digits and continues infinitely without pattern.

Pi Day

March 14 (3/14) is celebrated worldwide as Pi Day, coinciding with Einstein's birthday.

Ancient Knowledge

The Great Pyramid of Giza's ratio of perimeter to height is approximately 2π.

Pi in the Sky

NASA uses pi in space calculations, from landing rovers to orbital mechanics.