Sleep Cycle Calculator

Find recommended bedtimes based on your wake-up time and 90-minute sleep cycles.

Tool

Recommended sleep times

  • 9:45 PM (6 cycles)
  • 11:15 PM (5 cycles)
  • 12:45 AM (4 cycles)

Assumes 15 minutes to fall asleep and 90-minute sleep cycles.

How it works

The tool subtracts full 90-minute cycles from your desired wake-up time.

It includes a 15-minute average sleep latency before cycle timing starts.

Output provides practical bedtime options for 4, 5, or 6 cycles.

Examples

If you need to wake at 7:00 AM, the tool gives several bedtime options the night before.

Choose a cycle count based on your sleep target and schedule constraints.

FAQ

Why 90-minute cycles?

It is a common sleep-cycle estimate used for simple bedtime planning.

Is this medical advice?

No. This is a planning aid, not medical guidance.