ISO week calendar
Week 42 2027
ISO week 42 of 2027 runs from Monday, October 18, 2027 to Sunday, October 24, 2027.
Date Time Encyclopedia answer, with calculation details and assumptions below.
ISO weeks start on Monday and end on Sunday. Week 1 is the week containing the first Thursday of the ISO week-numbering year.
Snapshot
Week 42 2027
ISO week 42 of 2027 runs from Monday, October 18, 2027 to Sunday, October 24, 2027.
ISO weeks start on Monday and end on Sunday. Week 1 is the week containing the first Thursday of the ISO week-numbering year.
- Week starts
- Monday, October 18, 2027
- Week ends
- Sunday, October 24, 2027
- ISO year
- 2027
- Weeks in ISO year
- 52
ISO week 42, 2027
- MonOct 18, 2027Week start
- TueOct 19, 20272027-W42
- WedOct 20, 20272027-W42
- ThuOct 21, 20272027-W42
- FriOct 22, 20272027-W42
- SatOct 23, 20272027-W42
- SunOct 24, 2027Week end
Method
Find the Monday of ISO week 1, then add seven days for each week after it.
ISO week context
Week 42 2027 uses the ISO week-date system: weeks start Monday, end Sunday, and week 1 is tied to the first Thursday of the ISO year.
Compare nearby ISO weeks
Adjacent week pages help verify handoffs between reporting periods, sprints, payroll periods, and weekly plans.
Related Lookups
FAQ
When does this ISO week start?
Week 42 of 2027 starts on Monday, October 18, 2027.
When does this ISO week end?
Week 42 of 2027 ends on Sunday, October 24, 2027.