Wake times
Pick your alarm, and we will tell you when to turn the light off
Waking up hurts less when the alarm catches the end of a cycle rather than the middle of one. These pages count backwards from your wake time in whole cycles, add the fifteen minutes it actually takes to fall asleep, and tell you what your evening has to look like.
Work backwards from your alarm in 90 minute blocks and add fifteen minutes to fall asleep. For a 7am alarm that is 11:15pm for five cycles or 9:45pm for six. The number matters less than holding it seven days a week.
- Average sleep cycle
- 90 minAverage sleep cycleReal ones run 70 to 120
- Added to fall asleep
- 15 minAdded to fall asleepThe bit most calculators drop
- Wake times covered
- 11Wake times coveredEvery half hour, 4am to 9am
Waking up mid-cycle is why mornings hurt
Two people can both sleep seven hours and feel nothing alike. The difference is usually where in a cycle the alarm landed. Pulled out of deep sleep you get twenty minutes of grogginess and a morning you spend catching up with yourself. Surfacing from a light patch, you are more or less awake before you have decided to be.
Counting backwards in whole cycles stacks the odds in your favour, and it is free. What it cannot do is account for the night you actually had, which is what asmart alarm is for.
Before six
Early enough that the bedtime is the hard part, not the alarm.
- Waking up at 4:00am8:15pmLights out at 8:15pm for five full cycles, or earlier for six.
- Waking up at 4:30am8:45pmLights out at 8:45pm for five full cycles, or earlier for six.
- Waking up at 5:00am9:15pmLights out at 9:15pm for five full cycles, or earlier for six.
- Waking up at 5:30am9:45pmLights out at 9:45pm for five full cycles, or earlier for six.
Six to half seven
Where most working alarms land, and where a smart wake window earns its keep.
- Waking up at 6:00am10:15pmLights out at 10:15pm for five full cycles, or earlier for six.
- Waking up at 6:30am10:45pmLights out at 10:45pm for five full cycles, or earlier for six.
- Waking up at 7:00am11:15pmLights out at 11:15pm for five full cycles, or earlier for six.
- Waking up at 7:30am11:45pmLights out at 11:45pm for five full cycles, or earlier for six.
Eight and later
Later starts, late chronotypes, and the schedules that quietly drift.
Questions people ask
How do I calculate what time to go to bed?
Start at your alarm and subtract 90 minutes for each full sleep cycle you want, then subtract another fifteen minutes for the time it takes to fall asleep. Five cycles is seven and a half hours of sleep, which is the target most adults should hold.
Is the 90 minute sleep cycle real?
It is a real average rather than a fixed clock. Cycles run roughly 70 to 120 minutes and change length through the night, with more deep sleep early and more REM towards morning. The arithmetic gets you close, and an alarm that watches for a light moment covers the rest.
Does it matter more when I sleep or how long I sleep?
Both matter, and consistency is the one most people underrate. A steady seven hours beats a swinging eight, because a schedule that moves by three hours between weekdays and weekends leaves your body clock permanently catching up.
Elsewhere on the site
Different corner of the same problem.
- FeaturesSleep scoreThe sleep score is a single number for a night, sitting at the top of that night detail view. Underneath it are the parts that produced it, and across nights the insights cover 21 metrics in 7 groups plus long-run measures like sleep regularity and sleep debt.
- Sleep soundsDistant stormFar-off thunder helps at the start of the night because the slow rolling swells give your attention something easy to follow while it lets go, and it hurts later because every roll is a change in level, which is exactly what surfaces a light sleeper. Tock treats it as a fall-asleep aid and fades it out after half an hour by default.
- Tock for youNew parentsYou do not wake up to an alarm any more, you wake up to a small person, three or four times, and then you have to be a functioning adult by seven. The night is not so much short as it is in pieces.
- AlternativesTock vs RiseChoose Rise if planning your day around energy peaks and a running sleep debt is what actually changes your behaviour. Choose Tock if you want the alarm itself to be smarter, the night recorded from the phone, and a coach that can talk about what it heard.
- RoundupsThe best sleep apps for iPhone, sorted by what you're fixingFor iPhone, the best sleep app depends on the problem. Tock is the best all-round pick when the alarm and the morning are what is broken, Apple Health Sleep is the free place to start, Calm is for people who cannot fall asleep, AutoSleep is for Apple Watch owners, Rise is for sleep debt and SnoreLab is for snoring.
- Wake tonesGentle alarm soundsA gentle alarm works when it catches you at a light moment and fails when it lands in the heaviest part of your night, which is a timing problem rather than a volume one. Tock watches movement and sound across the 30 minutes before your alarm and rings early at a lighter moment if it finds one, with your set time as the fallback.
A steady schedule beats extra sleep
Tock tracks how consistent your nights actually are, not just how long they were, and rings a little early when it finds a lighter moment in the last half hour.