Wake-Up Time Calculator
Pick alarm time options from your bedtime, fall-asleep estimate and 90-minute sleep cycles, with age-based sleep-duration guidance.
Alarm options
Alarm options from 14:08 to 21:38. Fall-asleep time 14 minutes, reference range Adult (18-60).
Calculated from your local device time. Fall-asleep time: 14 min. Each option assumes a 90-minute sleep cycle and does not measure actual sleep stages.
Wake-up time calculator from bedtime
This page serves the narrower English intent: I am going to bed now or at a specific time, so what alarm times should I consider?
L is the estimated fall-asleep time in minutes. n is the number of complete 90-minute sleep cycles.
Choosing an alarm option
- One to three cycles are short-sleep options and should not be treated as a normal routine.
- Five to six cycles are usually closer to the common adult overnight sleep range.
- If you often take longer to fall asleep, increase the fall-asleep time so every alarm option shifts later.
- Use the timer or time calculator pages for general clock arithmetic; this page is sleep-cycle-specific.
Frequently Asked Questions
Sources and References
- About SleepCDC
- Brain Basics: Understanding SleepNINDS
- Sleep Phases and StagesNHLBI
- Seven or more hours of sleep per night: a health necessity for adultsAASM
Calculations are based on the listed reference sources. Links open in a new tab.
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