Check what week it is or select a date
Use this calculator to find the week number for any date. It follows ISO week standards, making it useful for business, planning, and scheduling.
A week number represents the position of a week within a year. The ISO system starts weeks on Monday and defines the first week as the one containing the first Thursday of the year.
Select a date or leave it empty to use today’s date. The calculator will instantly show the corresponding week number and year.
January 1, 2026 falls in Week 1 of 2026.
The ISO week date system is widely used internationally. Weeks start on Monday, and each week belongs to a specific year.
The week number is calculated based on ISO standards where weeks start on Monday.
This calculator shows the current week number automatically.
Yes, week numbering depends on the calendar year and ISO rules.
They provide a consistent way to track weeks across different countries and systems.