Sleep Calculator (Bedtime Optimizer)
Sleep Calculator finds the best bedtime or wake-up time based on 90-minute sleep cycles. Plan when to wake up or when to go to bed.
Last updated: July 2026
A sleep calculator tells you the best bedtime based on your wake-up time using 90-minute sleep cycles — waking at cycle end means you feel more rested.
How to use Sleep Calculator (Bedtime Optimizer)
- Choose: plan a wake-up time or plan a bedtime.
- Set your target time and how long to fall asleep.
- Read recommended times optimized around sleep cycles.
Frequently asked questions
How long is a sleep cycle?
Most adults cycle every 90 minutes. Waking at cycle end avoids sleep inertia.
Should I include time to fall asleep?
Yes — the calculator subtracts this from total sleep time.
Is this medical advice?
No — it's a general guide. Consult a doctor for sleep concerns.
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