ISO Week Number Calculator
Find the ISO week number for any calendar date. Calculate the ISO week year and number using Monday as the first day of the week.
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Result
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Calculation method
How to use ISO Week Number Calculator
Calculate the ISO week year and number using Monday as the first day of the week.
ExampleISO week 1 is the week containing the year’s first Thursday.
Displayed decimals can vary with the input and rounding method.
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