Sleep Diary
Sleep clinics don't start with gadgets — they start with a two-week diary. Fill in last night each morning (it takes a minute) and this diary computes the number clinicians actually watch: your sleep efficiency.
Last night
When you physically got into bed
When you started trying to sleep
When you woke for the last time
When you actually got up
This night: 6h 50m asleep of 8h 00m in bed → sleep efficiency 85.4%
What sleep efficiency tells you
Sleep efficiency is the share of time in bed that you are actually asleep: total sleep time ÷ time in bed. In CBT-I (cognitive behavioral therapy for insomnia, the first-line treatment), 85% or higher is the usual target zone. A low number with long hours in bed usually means the bed has become a place for lying awake — which is why CBT-I focuses on stimulus control (bed = sleep) and consistent wake times rather than “trying harder” to sleep. The fields in this diary follow the Consensus Sleep Diary, the standard format used in sleep research.
Pair the diary with the sleep hygiene checklist for the fixable basics, and give any change two weeks of data before judging it — single nights are noise.
This sleep diary is a self-tracking tool in the format used by sleep clinics. It does not diagnose insomnia or any sleep disorder, and it is not CBT-I treatment. If poor sleep persists for more than a few weeks or seriously affects your days, talk with a clinician — ideally one who offers CBT-I.
Frequently asked questions
How long should I keep a sleep diary?
Two weeks is the standard: long enough to cover workdays and weekends and to average out odd nights, short enough to stay doable. Sleep clinicians typically ask for 1–2 weeks before a first appointment, which is exactly what this tool produces.
What is a good sleep efficiency?
85% or above is the commonly used healthy zone; above 90% is typical of strong sleepers. Below 80% sustained over weeks suggests a lot of awake time in bed — the pattern CBT-I is designed to fix. Judge the two-week average, not any single night.
Should I estimate the times?
Yes — estimates are the standard. The consensus diary is designed for morning-after recall, not clock-watching (which itself worsens sleep). Round to the nearest quarter hour and don't check the time during the night.
Is my diary private?
Yes. Entries are stored only in your browser's local storage on this device, and you can delete any night or everything. Nothing is uploaded to a server.
Keep going
Your results from every tool are saved only in this browser — see them together on My Results.