Sleep diary

Log your nights, see your sleep efficiency, and get a suggested sleep window. Saved only in this browser.

Works offline. Nothing you enter leaves your browser.

How it works

Each morning, log when you got into bed, when you got up for the day, and roughly how long you slept. Guess; don’t check the clock during the night. Under More you can also note wake-ups, naps, your last caffeine, alcohol and anything else. That’s useful if you take the diary to a doctor.

Sleep efficiency = time asleep ÷ time in bed. 85% or more is one of the expert-agreed markers of good sleep quality [1].

The sleep window comes from sleep restriction, part of cognitive behavioral therapy for insomnia (CBT-I). The American Academy of Sleep Medicine suggests it for chronic insomnia [2]. The idea: spend only about as long in bed as you actually sleep, so the time you’re in bed becomes solid sleep. Then widen the window as your efficiency improves.

After 7 nights, the diary suggests a starting window. The rules follow the sleep restriction protocol used by Kyle and colleagues [3]:

1. Starting length: your average sleep over the last 7 nights, rounded to 15 minutes, and never less than 5 hours.
2. Timing: the window ends at your fixed wake time, so you go to bed no earlier than wake time minus the window.
3. Each week: if your sleep efficiency was 90% or more, add 15 minutes. From 85% to 89%, keep it. Below 85%, take away 15 minutes, but never go below 5 hours.

In that study of 16 people with insomnia, sleepiness and slower reactions rose during the first three weeks, and were back to normal by three months [3]. Don’t drive if you feel drowsy.

The full method, who it’s for and who should not try it alone are on the sleep restriction page. Read it before you start.

Your data

• Saved in this browser’s local storage, on this device only. Nothing is sent anywhere.
• Download CSV gives you a spreadsheet of every night. Do it now and then; clearing your browser data deletes the diary.
• Delete all removes everything, including your window. A single night can be deleted from its row.
• A two-week diary is also useful to bring to a doctor. See when to see a doctor.