December 31, 2035 (Monday) to January 6, 2036 (Sunday)
Week 1 of 2036 runs from December 31, 2035 (Monday) to January 6, 2036 (Sunday). This is the 1th week of the year according to the ISO 8601 standard, in which weeks start on Monday.
Dec 31 is a Monday. It is the first day of Week 1 of 2036.
Jan 6 is a Sunday. It is the last day of Week 1 of 2036.
Dec 31 is in Week 1 of 2036 according to ISO 8601.
Jan 6 is in Week 1 of 2036 according to ISO 8601.
Week 1 of 2036 runs from December 31, 2035 to January 6, 2036.
Week 1 of 2036 starts on December 31, 2035, the 365th day of 2035.
Yes, all 7 days of Week 1 of 2036 fall within 2036.
2036 has 53 weeks according to ISO 8601.