Week 1 1265: December 29, 1264 – January 4, 1265
Week 1 starts on Monday, December 29, 1264 and ends on Sunday, January 4, 1265.
Quick answer
Week 1 of 1265 is the seven-day ISO week from December 29, 1264 to January 4, 1265. ISO weeks always run from Monday to Sunday.
Dates for each day of this week
- Monday: December 29, 1264
- Tuesday: December 30, 1264
- Wednesday: December 31, 1264
- Thursday: January 1, 1265
- Friday: January 2, 1265
- Saturday: January 3, 1265
- Sunday: January 4, 1265
The planner opens with this Monday selected. Public holidays depend on your country and are not subtracted automatically.
Check the current work week
Need today’s week instead? Open the current work week dashboard for the live ISO week number, Monday-to-Sunday range, business days left and Friday planning date.
Use week 1 in professional planning
This permanent week reference can be used in project plans, payroll notes, weekly reports, production schedules and deadline documents. Share the week number together with the ISO year and exact date range to avoid ambiguity around New Year.
For calculations that span more than one week, use the weeks between dates calculator. For work schedules, compare the same range with the business days calculator or open the project timeline calculator.
Weeks around week 1
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FAQ
What are the dates for week 1 of 1265?
The dates are December 29, 1264 through January 4, 1265.
What day does this week start?
It starts on Monday.
What day does this week end?
It ends on Sunday.
How should I write this week in a report?
Use “ISO week 1 of 1265 (Dec 29–Jan 4, 1265)” so the week-year and date range are both clear.