Fibonacci Day 1685

Friday, 23 November 1685

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 1685?
Fibonacci Day 1685 is on Friday, 23 November 1685.
What day of the week is Fibonacci Day 1685?
It falls on Friday.
How is Fibonacci Day calculated?
This event is observed every year on 23 November.