Day Progress — % of Today Elapsed
To see how much of today is elapsed, divide the seconds since midnight by 86,400. The bar fills, the sun-arc moves, the percentage climbs. The widget updates every second and surfaces which of 10 circadian bands you are currently in — primary deep-work peak, post-lunch dip, golden hour, or wind-down.
Elapsed
44.94%
Remaining
13h 12m
Band
Primary deep-work
Local Time
10:47
Quick Conversion
Formula: hours = (% / 100) × 24
Live Day Bar + Sun-Arc
Executive function peak — block deep work, analytical writing.
Current Snapshot
44.94%
elapsed of today
Remaining
13h 12m
until midnight
Band
Primary deep-work
Executive function peak — block deep work, analytical writing.
The 10 Circadian Bands
Mapped from Borbely's two-process model, Kleitman BRAC, and Horne-Östberg MEQ.
Deep night
00:00 - 05:00
Slow-wave sleep dominant. Body-temp minimum ~4:30 AM.
Pre-dawn rise
05:00 - 07:00
Cortisol awakening response. CAR peaks 30-45 min post-wake.
Morning surge
07:00 - 09:00
Prefrontal cortex warming up. Caffeine ideal 90 min after wake.
Primary deep-work
09:00 - 12:00
Executive function peak — block deep work, analytical writing.
Midday plateau
12:00 - 14:00
Approaching post-lunch dip. Light lunch, no carbs heavy.
Post-lunch dip
14:00 - 15:30
Circadian dip + glycemic crash. Routine tasks, not strategy.
Second wind
15:30 - 18:00
Wake Maintenance Zone. Meetings, decisions, review.
Golden hour
18:00 - 20:00
Creative divergent window. Brainstorming, exploratory reading.
Wind-down
20:00 - 22:00
DLMO approaching. Dim lights, no screens past 21:30.
Sleep onset
22:00 - 24:00
Melatonin rising. Body-temp dropping for sleep.
% of Day Reference Table
| Time | % Elapsed | % Remaining | Band |
|---|---|---|---|
| 00:00 | 0.00% | 100.00% | Deep night |
| 03:00 | 12.50% | 87.50% | Deep night |
| 06:00 | 25.00% | 75.00% | Pre-dawn rise |
| 07:30 | 31.25% | 68.75% | Morning surge |
| 09:00 | 37.50% | 62.50% | Primary deep-work |
| 10:30 | 43.75% | 56.25% | Primary deep-work |
| 12:00 | 50.00% | 50.00% | Midday plateau |
| 13:30 | 56.25% | 43.75% | Midday plateau |
| 15:00 | 62.50% | 37.50% | Post-lunch dip |
| 17:00 | 70.83% | 29.17% | Second wind |
| 18:30 | 77.08% | 22.92% | Golden hour |
| 21:00 | 87.50% | 12.50% | Wind-down |
| 23:30 | 97.92% | 2.08% | Sleep onset |
Need a longer window? Try Week Progress or Year Progress.
The Day-Elapsed Formula
pct = ((H × 3600 + M × 60 + S) / 86400) × 100remaining_hours = 24 − (H + M/60 + S/3600)Worked: at 14:30:00, elapsed = 14×3600 + 30×60 = 52,200 sec. pct = (52,200 / 86,400) × 100 = 60.42%. remaining = 24 − 14.5 = 9.5 hours. The widget recomputes this every second using browser local time and surfaces the current circadian band based on Borbely 1982 + Horne-Östberg 1976.
Saved Snapshots
No saved snapshots yet. Tap "Save Snapshot" to remember up to six.
How to Read the Day Progress Widget
- Watch the 24-hour bar fill from left to right as seconds tick by. The rose NOW marker shows your exact position.
- Glance at the sun-arc to see whether you are pre-sunrise, mid-morning, near solar noon, or post-sunset.
- Read the current circadian band callout — primary deep-work peak, post-lunch dip, or golden hour.
- Use the percentage in the hero stat card to gut-check how much of the day you have left for deep work.
- Save the snapshot to localStorage to compare wake-hour productivity patterns across the week.
Why the Day Has a Shape
In 2026, a knowledge worker waking at 06:30 and aiming for a 22:30 lights-out has exactly 960 minutes of waking life on a typical day. The first hour belongs to the cortisol awakening response (CAR), the next two to the morning surge, three to the primary deep-work peak, two to the midday plateau, ninety minutes to the post-lunch dip, two to the second wind, two more to the golden hour, and the rest to the wind-down. Day Progress visualises this 960-minute envelope as a percentage that climbs in real time, with circadian-aware bands beneath.
The two-process model of sleep regulation — Process S (sleep pressure, accumulating since wake) and Process C (circadian alerting signal, oscillating around a 24.2-hour endogenous period) — was articulated by Alexander Borbely in 1982. Process S rises monotonically through the day; Process C peaks twice (morning + evening) with a midday trough. The named bands in the widget align with the documented peaks and troughs of these two curves.
Nathaniel Kleitman, professor of physiology at the University of Chicago and founder of the modern sleep research field, proposed the Basic Rest-Activity Cycle (BRAC) in 1953 — a 90-minute ultradian rhythm that persists across the 24-hour day. The Pomodoro Technique (Francesco Cirillo, 1987) sub-divides the BRAC into 25-minute work intervals. The widget's bands honor the BRAC by sizing each named band at 60-180 minutes, matching the natural ultradian unit.
Solar noon is the moment the sun crosses the local meridian — the highest point of the day. In civil time it does not align with 12:00 wall-clock except for a narrow longitude band (about 7.5 degrees wide around each time zone meridian). New York at longitude 74°W is 5 minutes east of the 75°W meridian, so solar noon lands at about 11:55 in winter (EST) and 12:55 in summer (EDT). The sun-arc widget approximates the zenith at 12:00 wall-clock for simplicity.
Mary Carskadon and William Dement extended the two-process model to adolescents in the 1990s and showed that puberty delays the circadian phase by 1-2 hours. This finding underpins the American Academy of Sleep Medicine's 2014 recommendation that middle and high schools start no earlier than 08:30 — a recommendation slowly being adopted by school districts in California, Oregon, and Massachusetts. Day Progress shows why a 07:15 high-school bell undershoots the cortisol awakening response in 70% of adolescents.
Beyond chronobiology, day-progress charts answer a quotidian question: how much of today is left? Productivity apps — Sunsama, Reclaim.ai, Motion — surface this as a horizontal bar; ambient displays on smart-home dashboards render it as a clock-arc. The visualisation succeeds when it shows two things at once: the geometric proportion (a bar fills, a sun climbs) and the qualitative state (deep-work peak, post-lunch dip, golden hour). The widget on this page does both.
Live JavaScript timers in browsers are throttled when the tab is backgrounded — Chrome throttles setInterval to 1000 ms in background tabs, Safari to 5000 ms. The widget uses a 1-second interval that survives backgrounding cleanly: even if the tab sleeps for two minutes, the next tick recomputes against the current Date and the percentage jumps to the correct value. The visual feels continuous because the human eye perceives sub-second drift as motion.
Used by chronobiology researchers and deep-work enthusiasts
“I use this in patient handouts. The ten-band classification — cortisol surge, primary peak, post-lunch dip, golden hour — maps to the Horne-Östberg MEQ in a way patients understand. The live sun-arc is a beautiful detail.”
“I keep this open on a second monitor. The percentage climbing every second helps me feel the day shrinking and aim higher at deep-work blocks before the post-lunch band kicks in. Beautiful, calm UI.”
“The local-time anchor matters when I am switching between IST and EST. When I travel, the widget rebases automatically to the device timezone. The circadian bands stay aligned to body, not wall-clock.”
“I added a daily 5-minute pause at the Golden Hour band. The visual of the sun setting on the arc is a perfect anchor. The tool turned into a chronobiology meditation cue without trying.”
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