Sleep cycle calculator
Enter your numbers — the results update instantly.
Best times to go to bed21:45 (6 × 90′) · 23:15 (5 × 90′) · 00:45 (4 × 90′)
If you go to bed now, wake at21:24 · 22:54 · 00:24
Worked example
Given: Wake-up time = 07:00; Time to fall asleep (min) = 15
Result: Best times to go to bed = 21:45 (6 × 90′) · 23:15 (5 × 90′) · 00:45 (4 × 90′); If you go to bed now, wake at = 21:24 · 22:54 · 00:24
How it is calculated
1. Enter the values you know. 2. The calculator converts them to base units and applies the formula. 3. The result is shown in the unit you choose.
Frequently asked questions
How do I calculate it?
Given: Wake-up time = 07:00; Time to fall asleep (min) = 15. Result: Best times to go to bed = 21:45 (6 × 90′) · 23:15 (5 × 90′) · 00:45 (4 × 90′); If you go to bed now, wake at = 21:24 · 22:54 · 00:24.
Is the calculator free and private?
Yes. It is free, needs no sign-up and runs in your browser — the numbers you type stay on your device.