What Week: Week 42
Find the calendar dates covered by any ISO week number.
ISO Week 42 of 2026 runs from October 12 to October 18, 2026, with roughly 10 ISO weeks remaining in the year after it. ISO 8601 weeks always run Monday through Sunday and belong to the year containing that week's Thursday, which is why the first few days of January sometimes belong to the final week of the previous year. Columbus Day falls within this week in 2026. Next year, 2027, the same week number runs from October 18 to October 24, 2027 instead, since the exact dates shift slightly every year.
As of October 1, 2026, 12:19 PM (America/New York).
Position in the Year
Week 42 falls in the second half of the year, roughly 81% of the way through 2026's 52-53 ISO weeks.
Quarter Overlap
This week sits in calendar Q4, based on its Monday (October 12).