Sleep Log
Free online sleep tracker. Log your bedtime, wake time, and sleep quality. See weekly averages, sleep debt, and a 14-night bar chart. All data stays in your browser — no signup required.
How to Use the Sleep Log
Enter the time you fell asleep and the time you woke up — the duration calculates automatically. Rate how rested you feel on a 1–5 star scale and add optional notes about anything that affected your sleep. The 14-night chart updates immediately, and the weekly average, sleep debt, and streak insights appear below. Log consistently for at least two weeks to start seeing meaningful patterns.
About This Tool
A private sleep journal that stores everything in your browser's localStorage. Log each night's bedtime, wake time, quality rating, and notes. The tool computes duration automatically, handles cross-midnight bedtimes, and shows a 14-night bar chart with color-coded bars relative to your sleep goal. Stats include 7-day average, sleep debt, best night, average quality, logging streaks, and a weekday-vs-weekend pattern insight. Export your data as CSV for backup or analysis. Pair with the Water Intake Logger and Medication Tracker for a complete daily health dashboard. This tool is for personal wellness tracking only — it is not a medical device.
Quick Reference Table
| Metric | Details |
|---|---|
| Recommended sleep | 7–9 hours per night for adults aged 18–64 (AASM/SRS) |
| Sleep debt | Cumulative shortfall vs. your goal over the last 7 logged nights |
| Quality rating | Subjective 1–5 star scale logged each morning |
| Bar chart | 14-night visual history with color-coded duration bars |
| Insights | Logging streak, goal streak, weekday vs. weekend pattern |
| Privacy | All data stored in localStorage — nothing leaves your device |
Frequently Asked Questions
Why does the tool identify sleep by wake date rather than bedtime?
Most nights straddle midnight — you go to sleep on Tuesday and wake up on Wednesday. Identifying a sleep session by its wake date is more intuitive and avoids ambiguity. When you log sleep for 'today', you are recording the sleep that ended this morning.
What does social jet lag mean?
Social jet lag describes the discrepancy between your biological clock and your social schedule. Most people sleep and wake later on weekends than weekdays, creating a weekly cycle of advancing and delaying their internal clock. Chronic social jet lag is associated with worse metabolic health, mood, and performance.
How accurate is a 1–5 star quality rating?
Self-reported sleep quality is subjective, but research shows it correlates meaningfully with objective measures from sleep studies. The key is consistency — rating your sleep on the same scale every morning reveals patterns over time.
My data disappeared — what happened?
Sleep log data is stored in your browser's localStorage, which is specific to the browser, device, and website origin. Data can be lost by clearing browser data, using private/incognito mode, or switching browsers. Use Export CSV regularly to keep a backup.