Metric and Gregorian, side by side
Metric Calendar retains the Gregorian year boundary and leap-year rule, while changing the divisions inside the year. Gregorian calendar context is documented by the U.S. Naval Observatory; Metric details come from the project specification.
| Feature | Gregorian | Metric proposal |
|---|---|---|
| Days per year | 365 or 366 | 365 or 366 |
| Year begins | January 1 | Same day as Gregorian January 1 |
| Months | 12; 28–31 days | 10; 36–37 days, or 38 in leap-year month 10 |
| Week | 7 continuous days | 6 days; extra days sit outside metric weeks |
| Month layout | Weekday of month start varies | Always starts with Focus Day 1 |
| Extra days | February 29 in leap years | Five Bonus Rest Days; Leap Day at year-end |
| Leap rule | Divisible by 4; centuries only if divisible by 400 | Same rule |
| Work schedule | Not defined by the calendar | Proposed 4 Focus + 2 Rest rhythm; actual schedules need agreement |
| Current role | Widely used civil calendar | A proposed framework and planning overlay |
Four days out of six is its own pattern
A four-day working week within a seven-day calendar and the Metric Calendar’s four Focus Days in a six-day cycle are different arrangements. Their day counts, spacing of rest, and relationship to existing weekends differ.
Before holidays and leave, a Monday–Friday pattern has 260–262 weekdays in a Gregorian year, depending on the year. The Metric structure has exactly 240 Focus Days. That is 20–22 fewer designated days, about 7.7–8.4% fewer than that particular baseline. These are calendar counts, not measured reductions in hours or forecasts of output.
At eight hours per Focus Day, the Metric pattern would imply 240 × 8 = 1,920 annual hours before leave or holidays. This is an illustration, not a required working-day length or a promise about pay. A person’s actual schedule could differ substantially.
In the regular six-day cycle, Focus Days occupy 4/6 of days. Across a common year, including Bonus Rest Days, the share is 240/365 ≈ 65.8%. Neither calculation establishes a health or productivity benefit. Read why shorter-workweek studies cannot directly validate this pattern.
Year alignment is preserved; month alignment changes
The proposal adds no change to the Gregorian year’s seasonal alignment: each Metric year covers exactly the same days as its Gregorian counterpart. The month labels divide those days differently.
Metric month boundaries use fixed ordinal positions. For example, month 03 begins on day 74: Gregorian March 15 in 2026, but March 14 in leap year 2028. A Gregorian date after February generally maps to a different Metric month/day in a leap year than in a common year.
Metric weeks restart within each month. Their Rest Days move relative to Gregorian weekdays, and Bonus Rest Days interrupt the regular six-day pattern. A recurring “every metric week” event therefore needs explicit month-aware scheduling; repeating an event every six elapsed days would eventually place it on the wrong metric weekday.
The practical trade-offs
What the structure offers
Predictable internal layouts
Each metric month has the same six regular weeks. The five two-month blocks each span 73 days in a common year. Regular Focus and Rest counts can be read directly from the specification.
What still takes work
Coordination with everyone else
Schools, religious observances, partners, reporting periods, and software often follow existing dates and weekdays. Ten months also cannot be divided into four equal groups of whole months for quarterly planning.
Predictable layouts are a property of the design. Less planning effort, lower burnout, or better performance are hypotheses. Any trial should measure both the potential gains and the burden of maintaining two systems.