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December 2028 Calendar

31 days, 21 of them working days. The number down the left is the ISO week; public holidays are not deducted, because which ones apply depends on where you are.

December31 days, 21 working
wkMoTuWeThFrSaSu
4827282930123
4945678910
5011121314151617
5118192021222324
5225262728293031

What the week numbers mean

These are ISO 8601 weeks: every week runs Monday to Sunday and belongs to the year that owns its Thursday. It is why 1 January 2027 falls in week 53 of 2026, and why a year has 53 weeks whenever it starts on a Thursday or is a leap year starting on a Wednesday. The US business convention of numbering from 1 January gives different answers, and payroll systems disagree about which one they mean.

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