Fibonacci clock
The Fibonacci clock tells the time with five squares whose sides follow the Fibonacci sequence: 1, 1, 2, 3 and 5. Together they form a golden rectangle.
Add up the red squares for the hour and the green squares for the minutes (in fives). Blue squares count for both, white ones for neither. Since most times can be made several ways, the pattern changes even when the time does not — a fun little puzzle for your desk.
Customise the fibonacci clock
How to use
- Switch clocks with ← →, by clicking or tapping the sides of the screen, or by swiping. The dice button (R) jumps to a random clock.
- Go full screen with the button in the top-right corner, a double-click or F.
- Open Customise (S) to change colours, fonts, 12/24-hour time, seconds, date and time zone. Settings are saved on this device.
Questions
- How do you read a Fibonacci clock?
- Hours = the sum of red and blue squares. Minutes = the sum of green and blue squares, times five. The dots underneath show the extra minutes (0–4).
More clocks
ClockFaces · Free online clocks