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Wake-Up Time Calculator
Enter your bedtime to find a wake-up time that fits your morning.
Go to bed at
15 min
Clock format
How to Use the Wake-Up Time Calculator
If your bedtime is fixed, start here. If your alarm is fixed instead, use the Bedtime Calculator to work backward.
- Enter the time you plan to go to bed.
- Adjust how long you usually take to fall asleep.
- Calculate suggested wake-up times.
- Choose a time that gives you enough sleep for your needs.
How Wake-Up Times Are Calculated
Wake-up time = bedtime + fall-asleep allowance + estimated sleep duration. For a 10 PM bedtime and a 15-minute allowance, 5:45 AM allows 7.5 hours of estimated sleep; 7:15 AM allows 9 hours. The tool uses 90-minute blocks and rounds up to five minutes.
Real sleep cycles vary between individuals and throughout the night. These times are planning estimates: waking at an estimated cycle boundary does not guarantee feeling refreshed. Total sleep duration and a consistent schedule also matter. Learn more about sleep cycles and the calculator methodology.
If you've been sleeping less than your target, use the Sleep Debt Calculator to estimate your shortfall over the past week.
Sources: CDC sleep-duration guidance and NHLBI sleep stages.
Editorial review by the Bedtime Calculator Editorial Team · . Review is editorial, not medical.
Quick answers
Wake-Up Time Calculator FAQs
What time should I wake up if I go to bed at 10 PM?
With 15 minutes to fall asleep, a 10 PM bedtime gives a 5:45 AM option for 7.5 hours of estimated sleep or 7:15 AM for 9 hours, both the next morning. Adjust the allowance and choose enough sleep for your needs.
What if I need to wake up at a fixed time?
Use the Bedtime Calculator to work backward from your required alarm and find a bedtime that allows enough sleep. You do not need to move your alarm to match a suggested cycle time.
Is it better to wake up at the end of a sleep cycle?
Not reliably. Sleep cycles vary, and this calculator cannot identify your sleep stages or guarantee an alert morning. Choose enough sleep for your needs and keep a consistent schedule.
Source: Understanding sleep cycles
How much sleep do adults need?
Adults aged 18–60 generally need at least seven hours of sleep each night; recommendations vary by age. Individual needs also vary, so choose a wake-up time that allows enough sleep for you.
Source: Sleep needs by age
Wake-Up Time Calculator benefits
Compare sleep durations
Compare options by how much sleep they allow.
Adjust your timing
Account for the time you usually take to fall asleep.
No account needed
Calculate sleep times without creating an account.
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