Week number and day of the year calculator
Find the ISO week number, weekday, day of the year, quarter and Australian financial year for any date.
How this calculator works
ISO 8601 weeks start on Monday, and week 1 is the week that contains the year's first Thursday. So 29 to 31 December can fall in week 1 of the next year. The Australian financial year runs from 1 July to 30 June.
Worked example: 29 October 2026 is a Thursday in ISO week 44. It's day 302 of 365, in Q4 and FY 2026–27.
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