Year calendar
Week Number 2021
Calculate and view week numbers for the year or a specific month. Select different standards to see how they compare.
Week numbers
2021 Calendar
ISO 8601 standard: Weeks start on Monday, and the first week of the year contains the first Thursday.
December 2020
January 2021
February 2021
March 2021
April 2021
May 2021
June 2021
July 2021
August 2021
September 2021
October 2021
November 2021
December 2021
Guide
2021 Calendar Guide
Current Week Number 2021
What week are we in 2021?
2021 has ended.
Week numbering follows the ISO 8601 standard, where Week 1 is the first week containing at least 4 days of January.
2021 Week Numbers and Financial Year
Standard Calendar Year 2021
The 2021 calendar year contains 52 weeks and 1 days.
Financial Year Week Numbers
Financial year week numbering varies by country:
- UK Financial Year 2021-2022: April 6, 2021 to April 5, 2022
- US Federal Fiscal Year 2021: October 1, 2020 to September 30, 2021
- Australian Financial Year 2021: July 1, 2020 to June 30, 2021
How Many Weeks in 2021?
2021 contains exactly 52 weeks and 1 extra day. Since 2021 is not a leap year:
- Total days: 365 days
- Complete weeks: 52 weeks (364 days)
- Remaining days: 1 days
Weeks in a Year 2021 Breakdown
- January 2021: 5 weeks + 3 days
- February 2021: 4 weeks
- March 2021: 5 weeks + 3 days
- April 2021: 5 weeks + 2 days
- May 2021: 6 weeks + 3 days
- June 2021: 5 weeks + 2 days
- July 2021: 5 weeks + 3 days
- August 2021: 6 weeks + 3 days
- September 2021: 5 weeks + 2 days
- October 2021: 5 weeks + 3 days
- November 2021: 5 weeks + 2 days
- December 2021: 5 weeks + 3 days
5 Week Months in 2021
Which Months Have Five Weeks in 2021?
Months with 5 weeks in 2021 (when counting Monday-to-Monday weeks):
- 1. March 2021 - 5 Mondays (1, 8, 15, 22, 29)
- 2. May 2021 - 5 Mondays (3, 10, 17, 24, 31)
- 3. August 2021 - 5 Mondays (2, 9, 16, 23, 30)
- 4. November 2021 - 5 Mondays (1, 8, 15, 22, 29)
How Many Mondays in 2021?
2021 contains 52 Mondays because:
- January 1, 2021 falls on a Friday
- Most days of the week appear 52 times in 2021
2021 Calendar Facts and Statistics
Key 2021 Calendar Information
- Leap Year: No (365 days)
- Starts on: Friday
- Ends on: Friday
- Total Weeks: 52 weeks + 1 days
- Weekdays: 261 days
- Weekend days: 104 days
Business Week Calculations 2021
Total business days: Approximately 261 days (excluding weekends)
Frequently Asked Questions
What week number is it right now in 2021?
2021 has ended. The current week number applies to the current year.
How are week numbers calculated?
Week numbers follow ISO 8601 standard:
- Week 1 contains the first Thursday of January
- Weeks start on Monday
- If January 1 falls on Friday, Saturday, or Sunday, it belongs to the previous year's last week
Why does 2021 have 52 Mondays?
2021 follows the standard pattern with 52 Mondays since it doesn't start on a Monday.
Do all countries use the same week numbering system?
No, some countries use different systems:
- ISO 8601 (most common): Week starts Monday
- US system: Week starts Sunday
- Middle East: Week starts Saturday
Reference
Week numbering standards used on this page
Week numbers above can be switched between three standards. Learn how each one calculates weeks: