Sleep calculator — when to go to bed to wake up refreshed

Enter when you need to wake to get bedtimes that match 90-minute sleep cycles, or enter a bedtime to find the best wake-up time.

Minutes

Fill in the form — the result appears here instantly

ℹ️ Results are estimates for planning. Real figures can differ with your situation and your bank or employer.

How it works: Sleep calculator

Sleep runs in cycles of about 90 minutes; waking at the end of one (light sleep) feels better than waking mid-cycle. Enter your wake-up time to get bedtimes for 3–6 cycles, including the time it takes to fall asleep (usually 10–20 minutes).

Adults need 7–9 hours (5–6 cycles), teenagers 8–10. Real cycles vary from 80 to 110 minutes.

FAQ

I wake at 6:00 — when should I sleep?

Around 20:45 or 22:15 (6 or 5 cycles, with 15 minutes to fall asleep).

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