ISO week details

Week 40 2011: October 3–9, 2011

Week 40 starts on Monday, October 3, 2011 and ends on Sunday, October 9, 2011.

Week40
ISO year2011
StartOct 3
EndOct 9

Quick answer

Week 40 of 2011 is the seven-day ISO week from October 3, 2011 to October 9, 2011. ISO weeks always run from Monday to Sunday.

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.

FAQ

What are the dates for week 40 of 2011?

The dates are October 3, 2011 through October 9, 2011.

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 2011 (Oct 3–Oct 9, 2011)” so the week-year and date range are both clear.