FIELD GUIDE / WEEK ORIGINS
Where does a week begin?
The dates do not move in time. Their positions move on the page. Change the origin below to re-fold February 2027 into seven-column rows.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
01 / Try every origin
Monday produces four complete rows. Tuesday through Sunday each produce five: the first Monday is preceded by one to six offset cells. The control changes both the weekday order and every date position—not just the headings.
02 / Convention, not astronomy
A seven-day cycle has no inherent left edge. ISO week numbering uses Monday, while Sunday-first layouts remain common in some regions. These conventions describe presentation and week numbering; neither changes the Gregorian date itself.
03 / Avoid a silent mismatch
Always declare the week origin next to a grid. A reader may otherwise treat the first column as their familiar starting day. Weekends are Saturday and Sunday here regardless of their column positions.