What week is it? Handy for weekly reports, scheduling, and dev sprints
W--
Calculating…
—
This week
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Weeks this year
Look Up Any Date's Week Number
ISO week number—
Week starts (Monday)—
Week ends (Sunday)—
Day of week—
💡 This tool uses the international ISO 8601 week numbering: weeks start on Monday, and week 1 is the week containing the year's first Thursday.
So Dec 29 – Jan 3 may count as next year's W1, and Jan 1 may still be the previous year's W52/W53 — which can differ by 1 week from Excel's default WEEKNUM. Agree on one system before numbering weekly reports.