Health & Fitness
Sleep Quality Journal & Pattern Logger
Log your bedtime, wake time, and sleep quality each day. Track average sleep duration and quality trends over time. All data is stored locally in your browser.
Log Sleep
Quality:Good
No sleep entries yet. Log your first night above.
Data stored locally in your browser only.
Sleep stages
| Stage | Type | Duration (per cycle) | Function |
|---|---|---|---|
| N1 (NREM 1) | Light sleep | 1–5 min | Transition from wakefulness |
| N2 (NREM 2) | Light sleep | 10–25 min | Memory consolidation, body temperature drops |
| N3 (NREM 3) | Deep/slow wave sleep | 20–40 min | Physical restoration, immune function, growth hormone |
| REM | Dream sleep | 10–60 min (increases each cycle) | Emotional processing, memory, creativity |
Sleep cycle length
A complete sleep cycle takes approximately 90 minutes. Adults need 5–6 cycles (7.5–9 hours) per night. Waking up at the end of a cycle (rather than mid-cycle) reduces sleep inertia - the groggy feeling after waking.
How to log sleep
To get useful data from the tracker, log consistently each day. The most important entries are:
- Bedtime: the time you turned off the lights and attempted to sleep.
- Sleep time: estimated time you actually fell asleep (often 10–20 minutes after bedtime).
- Wake time: the time you woke up for the day.
- Nighttime awakenings: how many times and roughly how long you were awake during the night.
Sleep quality indicators
- Sleep efficiency: the percentage of time in bed you were actually asleep. Formula: (total sleep time ÷ time in bed) × 100. Normal efficiency is 85% or higher.
- Sleep onset latency: how long it takes to fall asleep after lights out. Under 20 minutes is typical; consistently over 30 minutes suggests difficulty falling asleep.
- WASO (Wake After Sleep Onset): total time spent awake after initially falling asleep. Under 30 minutes is typical for adults.
Warning signs
- Consistently sleeping fewer than 6 hours per night is associated with increased risk of cognitive impairment, cardiovascular disease, and metabolic issues.
- Insomnia criteria (DSM-5): difficulty initiating or maintaining sleep at least 3 nights per week for at least 3 months, with daytime impairment. If this describes your pattern, consult a physician.
Sleep hygiene checklist
- Keep consistent wake and bedtimes, including weekends.
- Avoid screens (phone, TV, laptop) 30–60 minutes before bed or use blue light filters.
- Keep your bedroom cool (16–19°C / 60–67°F) and dark.
- Avoid caffeine after 2 PM; avoid alcohol within 3 hours of bedtime.
- Exercise regularly, but not within 1–2 hours of bedtime for most people.
- If you can't sleep, leave bed and do something calm until sleepy - don't lie awake for long periods.