Sleep Calculator
Calculate your optimal wake-up times and bedtimes using 90-minute sleep cycles (NREM + REM) and age recommended ranges.
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Quick Summary: Sleep Calculator
In FY 2026-27, science suggests that humans sleep in 90-minute cycles. Waking up at the completion of a cycle (e.g., 6h, 7.5h, or 9h) prevents 'sleep inertia' and ensures you wake up alert rather than groggy.
How to use the Sleep Calculator
- 1
Choose Intent
Select whether you want to calculate when to wake up (based on now) or when to go to bed (based on a wake-up time).
- 2
Set Parameters
Adjust for 'Sleep Onset Latency' (how long it takes you to fall asleep).
- 3
Pick Your Time
Choose from the recommended cycle-aligned times for optimal rest.