Week 40 1255: October 4–10, 1255
Week 40 starts on Monday, October 4, 1255 and ends on Sunday, October 10, 1255.
Quick answer
Week 40 of 1255 is the seven-day ISO week from October 4, 1255 to October 10, 1255. ISO weeks always run from Monday to Sunday.
Dates for each day of this week
- Monday: October 4, 1255
- Tuesday: October 5, 1255
- Wednesday: October 6, 1255
- Thursday: October 7, 1255
- Friday: October 8, 1255
- Saturday: October 9, 1255
- Sunday: October 10, 1255
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 40 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 40
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FAQ
What are the dates for week 40 of 1255?
The dates are October 4, 1255 through October 10, 1255.
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 40 of 1255 (Oct 4–Oct 10, 1255)” so the week-year and date range are both clear.