Sleep Ledger

Your sleep, day by day

Last night
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No nights recorded
7-day average
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0 nights recorded
30-day average
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0 nights recorded
Goal streak
0 nights
Build your rhythm
READY FOR TONIGHT

Sleep session

Tap when you go to sleep. Tap again when you wake up.

Sleep cycle calculator

Estimated bedtimes for your saved wake time.

Right now—
Target wake time—
Loading your saved wake time…

Upcoming estimated bedtimes

Earlier options allow more sleep

    If you’re tired now, don’t stay awake just to reach a calculated time. These estimates don’t replace your sleep goal.

    About these estimates

    Each option works back from your next target wake time using a 90-minute cycle estimate, then subtracts your time to fall asleep. Times already passed are left out. Your target wake time and sleep goal come from your existing Settings.

    Real sleep cycles vary; NIH describes cycles of about 80–100 minutes. This app cannot detect sleep stages or predict the easiest moment to wake. Getting enough sleep still matters, even when you feel less groggy after a shorter night.

    The calculator is a planning tool. It does not set an alarm or start a sleep session. Use your usual two buttons to record your night.

    Sleep Duration

    0 nights recorded this year

    Your goal: 8h · perfect 8–10h

    Sleep Quality

    Based on your bedtime and wake time.

    Your schedule: 11 pm – 7 am

    This chart measures timing against your personal schedule. It cannot measure sleep stages, interruptions, or how rested you feel.

    Your sleep patterns

    More insights from the same two taps.

    Typical bedtime
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    Past 7 days
    Typical wake time
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    Past 7 days
    Timing variation
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    Log at least 2 nights
    Goal shortfall
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    Past 7 days · recorded nights only
    Nights on goal
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    Past 30 days
    Weekend shift
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    Log 2 weekday and 2 weekend nights
    How these numbers work

    Typical times average your clock times over the past 7 days, including times around midnight. Timing variation is the average difference from those typical bedtimes and wake times; lower means more consistent.

    Goal shortfall adds the hours below your chosen goal on recorded days. Extra hours on another day do not subtract from it. Nights on goal uses your full perfect range over the past 30 days.

    Weekend shift compares the middle of your sleep on Saturday/Sunday wake dates with weekday wake dates over the past 30 days. Timing statistics use each day’s longest session and its recorded time zone. Missing days are left out.

    The focus on regular timing follows NIH sleep guidance. CDC explains sleep duration and quality. These are summaries of your logs; goal shortfall is not a measure of medical sleep debt.

    Recent nights

    Bedtime, wake time, and the hours between.

    A fresh start

    Your first night will appear here.

    hours

    Green falls inside your range. Colors get warmer further away.

    Sleep Quality schedule

    The quality chart compares your times with this schedule. Within 30 minutes on average gets the best green.

    Your records

    Records stay on this device. Keep a backup in Files before clearing website data or changing phones.

    Choose your times

    1. Open this website in Safari.
    2. Tap Share, then Add to Home Screen.
    3. Keep Open as Web App on if shown, then tap Add.

    Use the Home Screen icon each time. Your records stay in the app on this device.