🗓️ Week Calculator
Enter a date to find which week of the year it falls in, plus how many weeks remain until year’s end.
What this calculator does
The Week Calculator tells you which week of the year a given date falls in, using the ISO 8601 standard where week 1 is the week containing the year’s first Thursday and weeks run Monday through Sunday.
How it works
Enter a year, month, and day. The calculator works out the day’s position in the year, then applies the ISO week-numbering rule to find its week number. It also reports how many days and weeks remain until the end of that calendar year.
Week numbering is widely used in business planning, payroll, and project scheduling. Note that some countries and systems (like the US retail calendar) number weeks differently, so figures may not match every calendar you encounter.