Week Progress Calculator
ISO week 2 of 2026 is 0.00% charged, with 7 days left. We measure the fraction of the current Monday-to-Sunday week elapsed and light a 7-segment battery one day at a time.
Week charged
0.00%
Days remaining
7
Today
Mon · 1/7
ISO week
#2
Quick Conversion
Formula: % = (weekday ÷ 7) × 100
The Live Week Battery
Today
Monday (day 1/7)
Days remaining
7
Time to week-end
7d 00h 00m 00s
Day-by-Day Charge
ISO week 2 runs 1/5/2026 to 1/11/2026.
Week Charge by End of Each Day
The percent of the ISO week complete at the final midnight of each day.
ISO Weekday → Percent of Week
| ISO day | Name | % at start of day | % at end of day | Days left |
|---|---|---|---|---|
| 1 | Monday | 0.00% | 14.29% | 6 |
| 2 | Tuesday | 14.29% | 28.57% | 5 |
| 3 | Wednesday | 28.57% | 42.86% | 4 |
| 4 | Thursday | 42.86% | 57.14% | 3 |
| 5 | Friday | 57.14% | 71.43% | 2 |
| 6 | Saturday | 71.43% | 85.71% | 1 |
| 7 | Sunday | 85.71% | 100.00% | 0 |
Place this week in the year with the Week of Year wheel, or zoom out to the month with Month Progress.
The Week-Progress Formula
progress% = (now − Monday 00:00:00) ÷ 604,800 s × 100ISO week 1 = the week containing the year's first Thursday (the week with Jan 4)Worked example: at midnight ending Wednesday (ISO day 3 complete), 3 days = 259,200 seconds have elapsed. progress = 259,200 ÷ 604,800 × 100 = 42.86%. By midnight ending Thursday the figure is 4 ÷ 7 = 57.14%, so the true 50% midpoint falls at midnight between Wednesday and Thursday.
ISO 52- vs 53-Week Years
| Year | ISO weeks | Reason |
|---|---|---|
| 2024 | 52 | starts Monday, leap |
| 2025 | 52 | starts Wednesday |
| 2026 | 53 | starts Thursday |
| 2027 | 52 | starts Friday |
| 2020 | 53 | leap starting Wednesday |
| 2032 | 53 | leap starting Thursday |
Your Saved Snapshots
No snapshots yet. Tap "Save snapshot to history" to record the battery charge and compare it later in the week.
How to Read the Week Battery
- Open the page — the battery shows seven day segments from Monday (day 1) to Sunday (day 7), following the ISO 8601 week.
- Fully charged amber segments are days that have passed; today's segment carries a white ring and charges from the bottom up through the day; dim indigo segments are still ahead.
- Read the headline charge percentage and the days-remaining countdown; both recompute every second from new Date().
- Note the ISO week number in the badge — week 1 is the week containing the year's first Thursday — so it matches your calendar app and spreadsheets.
- Tap Save snapshot to store the charge level in localStorage and compare it as the week fills.
Why Week Progress Matters
In 2026, a developer pushing to close a Friday-afternoon ticket wants a blunt answer to a simple question: how much of the working week is already gone? Week Progress shows it as a 7-segment battery — Monday through Sunday — that charges one segment per day, with today's segment pulsing and the headline reading the exact percent of the week elapsed. Because it follows the ISO 8601 week, every week begins on Monday and the percentage is computed live against the full 7-day, 604,800-second span.
The week the tool measures is the ISO 8601 week, the international standard published by the International Organization for Standardization that fixes Monday as day 1 and Sunday as day 7. This matters because the United States, Canada, and Japan conventionally treat Sunday as the first day of the week, while ISO 8601 — used across Europe and in virtually all software date libraries — starts on Monday. Week Progress follows the ISO convention so it agrees with the week numbers printed in spreadsheets, planners, and scheduling systems worldwide.
ISO 8601 also defines the week number: week 1 of any year is the week containing that year's first Thursday, equivalently the week containing January 4. A consequence is that the first days of January can belong to week 52 or 53 of the previous year, and the last days of December can belong to week 1 of the next year. A long ISO year has 53 weeks; most have 52. The week-number badge on this page applies that rule exactly, so it never disagrees with a calendar app.
The battery metaphor is deliberate. Unlike a smooth bar, a battery shows discrete charge cells, which matches how people experience a week — as seven distinct days, not as a continuous slosh of time. Monday lights first, the segments fill left to right, today's cell glows, and the weekend cells (Saturday and Sunday) are tinted differently so the work-week boundary is visible at a glance. The charge percentage on the battery is the same figure as the headline percent of the week.
Weekly cadence is the heartbeat of modern work. Agile sprints, stand-ups, payroll weeks, content schedules, and habit streaks all run on a seven-day cycle, and Nathaniel Kleitman's mid-twentieth-century work on biological rhythms plus the broader 'weekly cycle' literature show that human mood and productivity themselves fluctuate predictably across the week. Seeing the battery at 71% on a Friday morning is a sharper nudge than a date alone to triage what still must ship before the weekend.
Pair Week Progress with its siblings for a complete view: the Year Progress thermometer tracks the calendar year, the Month Progress calendar grid fills the current month day by day, and the Week of Year wheel places this ISO week among the 52 or 53 spokes of the year. Each answers 'how far through am I?' at a different scale.
Everything is computed client-side from a single new Date() call on a one-second interval, so the battery, the days-remaining countdown, and the today-glow all reflect your own time zone and update live. A small localStorage history panel records your saved snapshots so you can compare the week's charge level across days.
Trusted by engineers, coaches, and payroll teams
“ISO weeks are how our whole org schedules, so a Monday-start battery that also shows the correct ISO week number is exactly right. Seeing it hit 71% on Friday morning is a great forcing function for the team.”
“My clients commit to weekly targets, and the segmented battery makes 'three of seven days done' immediately obvious. The discrete cells beat a smooth bar — people count days, not percentages.”
“We run a Monday-to-Sunday pay week, so the ISO alignment matters. I keep this open during cutoff to see exactly how much of the week is left before timesheets lock.”
“I explain the ISO 8601 first-Thursday week-numbering rule to readers, and being able to point them at a live battery that uses the exact same rule saves me a thousand words of explanation.”
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