Weekmark

Calendar week · ISO 8601

Week 40, 2027

Monday 4 October – Sunday 10 October 2027

  1. Mon4Oct
  2. Tue5Oct
  3. Wed6Oct
  4. Thu7Oct
  5. Fri8Oct
  6. Sat9Oct
  7. Sun10Oct
ISO week
2027-W40
Copy as
CW40 (4–10 Oct)
Quarter
Q4 2027
Weeks in 2027
52
US week number
41

Week 40 is also written KW 40 (Kalenderwoche) or CW 40. ISO weeks start on Monday, and week 1 is the week with the year’s first Thursday. US calendars start weeks on Sunday and count the week with 1 January as week 1, so they give Monday 4 Oct to Saturday 9 Oct a different number: week 41.