Bedtime Calculator
Know exactly when you need to be in bed to hit your specific sleep duration target. We factor in the time it takes to fall asleep.
Fill out the form to see your recommended bedtime.
How this differs from the Sleep Calculator
Our standard Sleep Calculator only gives you times based on strict 90-minute intervals to avoid waking up mid-cycle. This Bedtime Calculator is for when you simply want to know when to get in bed to achieve a specific number of hours of sleep, regardless of cycles.
Choosing your target duration
This calculator takes whatever duration you set and works backwards from your wake time, adding time to fall asleep. It does not round to sleep cycles — that is what the Sleep Calculator is for.
If you are unsure what to set: the CDC's guidance for adults aged 18 to 60 is 7 or more hours per night, with 7 to 9 hours for ages 61 to 64 and 7 to 8 hours for 65 and older (CDC).
Within those ranges, individual need varies. The practical test is how you feel across several consistent nights, not a single night.
Why we add time to fall asleep
Getting into bed is not the same as being asleep. Most people need somewhere in the range of 10 to 20 minutes, so we add a buffer — otherwise a target of 8 hours quietly becomes 7 hours 45.
If you know you fall asleep much faster or much slower than average, adjust the result accordingly.
Making the bedtime stick
A calculated bedtime only helps if you can keep it. General sleep guidance consistently points to the same basics: going to bed and getting up at the same times each day, keeping the bedroom quiet, dark and cool, avoiding large meals and alcohol before bed, and avoiding caffeine in the afternoon and evening (CDC).
A bedtime 30 minutes earlier that you actually keep is worth more than one two hours earlier that you don't.
Common questions
Is this different from the Sleep Calculator?
Yes. This one hits a specific number of hours. The Sleep Calculator rounds to full sleep cycles. Use this when the total matters more; use that one when morning grogginess is the problem.
What if I can't fall asleep at the time it gives me?
Shifting a sleep schedule usually works better in small steps than in one jump. Moving your bedtime by 15 to 30 minutes at a time is generally easier to sustain.
Does the wake time matter more than the bedtime?
Keeping a consistent wake time is often the easier anchor, since it is less affected by how your evening goes.
Related guides
Sources
General information about sleep stages and cycles is based on published guidance from the National Heart, Lung, and Blood Institute (NIH). Sleep duration recommendations are based on guidance from the CDC.