Choose when you want to wake up and how long you want to sleep — we'll suggest a bedtime, including CDC-recommended duration ranges by age.
Everything is calculated on your device. Your times are never sent to our servers, saved in cookies, or shared with analytics.
The time your alarm goes off, in your local time.
Practical options near the recommended range for the age group you picked — not guaranteed requirements. Individual needs vary.
If you usually need extra minutes to drift off, add them here. This is your own estimate, not a medical statement about sleep latency.
For the full recommended range you would go to bed between 10:00 PM and 11:00 PM.
This bedtime falls before midnight, on the previous calendar day.
Pick an age group to see the CDC's recommended sleep durations: 8–10 hours for ages 13–17, at least 7 hours for ages 18–60, 7–9 hours for ages 61–64, and 7–8 hours for ages 65 and older. The bedtime is then wake time minus the chosen duration (minus your optional fall-asleep estimate), computed in whole minutes so times that cross midnight are handled correctly and displayed in your locale's clock format.
The calculator does not assume anyone has exactly 90-minute sleep cycles and does not round bedtimes to cycle boundaries — sleep cycles vary between people and across the night. Recommendations are population guidance; your own sleep needs may be higher or lower.
bedtime = wake time − (sleep duration + optional fall-asleep time)
Sleep cycles are not exactly 90 minutes for everyone — they vary between people and change across the night. Rounding to fixed cycles would give false precision, so the calculator simply subtracts your chosen duration from your wake time.
Run the calculation once for each wake-up time you use, or pick the wake time that matters most (for example work days).
No. They are CDC recommendations for general health. The selectable durations are practical options within or near each recommended range, not guarantees.
No. This is a scheduling tool. If you have concerns about your sleep, talk to a healthcare professional.
This calculator is a scheduling aid for educational purposes, not medical advice. It cannot diagnose sleep disorders or assess sleep quality. Talk to a healthcare professional about persistent sleep problems, and never ignore excessive daytime sleepiness or sleepiness while driving.
We regularly improve our tools. Found a problem or have a suggestion? We're listening.