Fibonacci Day 1221

Tuesday, 23 November 1221

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 1221?
Fibonacci Day 1221 is on Tuesday, 23 November 1221.
What day of the week is Fibonacci Day 1221?
It falls on Tuesday.
How is Fibonacci Day calculated?
This event is observed every year on 23 November.