Week numbers for 2009
View all week numbers for 2009 in the table below. Each week shows its start and end date according to the ISO 8601 standard.
This is a special year with 53 weeks instead of the usual 52 weeks.
| Week Numbers 2009: | Start date: | End date: |
|---|---|---|
| week 1 | Mon, Dec 29, 2008 | Sun, Jan 4, 2009 |
| week 2 | Mon, Jan 5, 2009 | Sun, Jan 11, 2009 |
| week 3 | Mon, Jan 12, 2009 | Sun, Jan 18, 2009 |
| week 4 | Mon, Jan 19, 2009 | Sun, Jan 25, 2009 |
| week 5 | Mon, Jan 26, 2009 | Sun, Feb 1, 2009 |
| week 6 | Mon, Feb 2, 2009 | Sun, Feb 8, 2009 |
| week 7 | Mon, Feb 9, 2009 | Sun, Feb 15, 2009 |
| week 8 | Mon, Feb 16, 2009 | Sun, Feb 22, 2009 |
| week 9 | Mon, Feb 23, 2009 | Sun, Mar 1, 2009 |
| week 10 | Mon, Mar 2, 2009 | Sun, Mar 8, 2009 |
| week 11 | Mon, Mar 9, 2009 | Sun, Mar 15, 2009 |
| week 12 | Mon, Mar 16, 2009 | Sun, Mar 22, 2009 |
| week 13 | Mon, Mar 23, 2009 | Sun, Mar 29, 2009 |
| week 14 | Mon, Mar 30, 2009 | Sun, Apr 5, 2009 |
| week 15 | Mon, Apr 6, 2009 | Sun, Apr 12, 2009 |
| week 16 | Mon, Apr 13, 2009 | Sun, Apr 19, 2009 |
| week 17 | Mon, Apr 20, 2009 | Sun, Apr 26, 2009 |
| week 18 | Mon, Apr 27, 2009 | Sun, May 3, 2009 |
| week 19 | Mon, May 4, 2009 | Sun, May 10, 2009 |
| week 20 | Mon, May 11, 2009 | Sun, May 17, 2009 |
| week 21 | Mon, May 18, 2009 | Sun, May 24, 2009 |
| week 22 | Mon, May 25, 2009 | Sun, May 31, 2009 |
| week 23 | Mon, Jun 1, 2009 | Sun, Jun 7, 2009 |
| week 24 | Mon, Jun 8, 2009 | Sun, Jun 14, 2009 |
| week 25 | Mon, Jun 15, 2009 | Sun, Jun 21, 2009 |
| week 26 | Mon, Jun 22, 2009 | Sun, Jun 28, 2009 |
| week 27 | Mon, Jun 29, 2009 | Sun, Jul 5, 2009 |
| week 28 | Mon, Jul 6, 2009 | Sun, Jul 12, 2009 |
| week 29 | Mon, Jul 13, 2009 | Sun, Jul 19, 2009 |
| week 30 | Mon, Jul 20, 2009 | Sun, Jul 26, 2009 |
| week 31 | Mon, Jul 27, 2009 | Sun, Aug 2, 2009 |
| week 32 | Mon, Aug 3, 2009 | Sun, Aug 9, 2009 |
| week 33 | Mon, Aug 10, 2009 | Sun, Aug 16, 2009 |
| week 34 | Mon, Aug 17, 2009 | Sun, Aug 23, 2009 |
| week 35 | Mon, Aug 24, 2009 | Sun, Aug 30, 2009 |
| week 36 | Mon, Aug 31, 2009 | Sun, Sep 6, 2009 |
| week 37 | Mon, Sep 7, 2009 | Sun, Sep 13, 2009 |
| week 38 | Mon, Sep 14, 2009 | Sun, Sep 20, 2009 |
| week 39 | Mon, Sep 21, 2009 | Sun, Sep 27, 2009 |
| week 40 | Mon, Sep 28, 2009 | Sun, Oct 4, 2009 |
| week 41 | Mon, Oct 5, 2009 | Sun, Oct 11, 2009 |
| week 42 | Mon, Oct 12, 2009 | Sun, Oct 18, 2009 |
| week 43 | Mon, Oct 19, 2009 | Sun, Oct 25, 2009 |
| week 44 | Mon, Oct 26, 2009 | Sun, Nov 1, 2009 |
| week 45 | Mon, Nov 2, 2009 | Sun, Nov 8, 2009 |
| week 46 | Mon, Nov 9, 2009 | Sun, Nov 15, 2009 |
| week 47 | Mon, Nov 16, 2009 | Sun, Nov 22, 2009 |
| week 48 | Mon, Nov 23, 2009 | Sun, Nov 29, 2009 |
| week 49 | Mon, Nov 30, 2009 | Sun, Dec 6, 2009 |
| week 50 | Mon, Dec 7, 2009 | Sun, Dec 13, 2009 |
| week 51 | Mon, Dec 14, 2009 | Sun, Dec 20, 2009 |
| week 52 | Mon, Dec 21, 2009 | Sun, Dec 27, 2009 |
| week 53 | Mon, Dec 28, 2009 | Sun, Jan 3, 2010 |
What is a week number?
A week number is the sequential number assigned to each week in a calendar year. We use the ISO 8601 international standard, where each week begins on Monday and runs through Sunday.
Calendar with week numbers
The calendar consists of 12 months. To reference smaller time periods, week numbers provide a convenient solution. Many activities are scheduled for a specific week when an exact date isn't yet confirmed. Week numbers offer a practical way to communicate these timeframes.
Week numbers for 2009
Every week runs from Monday to Sunday. Week 1 is the week with the first Thursday of January, following the ISO 8601 standard used in business, logistics and most of the world outside the US.
The current week number is determined by the date. January 4 always falls in the first week of the year - this is the standard rule. Because of this, February 1 always falls in week 5.
You can calculate the current week number yourself by counting the elapsed weeks or checking a calendar. However, this is time-consuming, which is why we provide a complete overview for each year showing all week numbers with their start and end dates.
What is the week number this week?
Week numbers are particularly important for maintaining organized schedules and coordinating with others. Our tools make it easy to track week numbers throughout the year.
FAQ
How many weeks are in 2009?
The year 2009 has 53 weeks. This is determined by the ISO 8601 standard where week 1 is the first week with at least 4 days in January.
When does week 1 of 2009 start?
Week 1 of 2009 begins on the Monday closest to January 1, as long as at least 4 days fall in January.
How are week numbers determined?
We use the ISO 8601 international standard. Each week starts on Monday, and week 1 is the first week with at least 4 days in the new year. This means January 4 always falls in week 1.
See also: Calendar 2009