23/11/2025
Fibonacci Day is celebrated every 23rd of November (11/23) because the date itself 1, 1, 2, 3 represents the beginning of the famous Fibonacci sequence. The celebration began in the early 2000s when math enthusiasts and educators started promoting the day online to honor Leonardo of Pisa, popularly known as Fibonacci, an Italian mathematician from the 12th century.
Fibonacci introduced the sequence to the western world through his book Liber Abaci in 1202. Over time, people realized how important the sequence is in nature, art, architecture, computer science, and even finance. As social media grew, so did the popularity of Fibonacci Day. Today, math lovers use the day to share fun facts, puzzles, spirals, and the beauty of numbers.