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Sleep Calculator

Free online sleep calculator — find the best bedtime or wake-up time based on 90-minute sleep cycles. Wake up refreshed and energized every morning.

Sleep tips for students

1

Keep a consistent sleep schedule — even on weekends.

2

Avoid screens at least 30 minutes before bed.

3

Keep your room cool, dark, and quiet for deeper rest.

4

Don't consume caffeine after 2 PM.

5

Aim for 5–6 complete sleep cycles (7.5–9 hours).