Sleep Calculator in Countdawns app

Sleep Calculator

Wake up feeling refreshed by aligning your sleep schedule with natural 90-minute sleep cycles. Enter when you need to wake up, and this calculator tells you the best times to fall asleep. Or enter when you are going to bed, and it will tell you the optimal wake-up times. Stop waking up in the middle of a deep sleep cycle.

Sleep Calculator

Calculate optimal sleep and wake times based on 90-minute sleep cycles.

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How it works

Choose your mode: I need to wake up at a certain time, or I am going to bed now. The calculator uses the standard 90-minute sleep cycle to compute optimal sleep and wake times. It accounts for the average 15 minutes it takes to fall asleep and recommends times based on completing 4, 5, or 6 full sleep cycles (6, 7.5, or 9 hours of sleep). For daily sleep schedule tracking, Countdawns for Android can help you set recurring bedtime and wake-up reminders.

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