Fibonacci Day 1491

Monday, 23 November 1491

Fibonacci Day uses the month and day notation 11/23 to echo the opening numbers of the Fibonacci sequence: 1, 1, 2, 3.

Frequently asked questions

When is Fibonacci Day 1491?
Fibonacci Day 1491 is on Monday, 23 November 1491.
What day of the week is Fibonacci Day 1491?
It falls on Monday.
How is Fibonacci Day calculated?
This event is observed every year on 23 November.