ISO 8601 weeks
This week is
W20
of 2026
Q2 · 33 weeks remaining
Right in the middle of things.
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That date falls in W20 of 2026 — the week of Monday, May 11, 2026.
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Monday
Monday, May 11, 2026
Sunday
Sunday, May 17, 2026
ISO 8601 weeks start on Monday. Week 1 is the week containing the year's first Thursday — which is why W1 sometimes starts in December. Years can have 52 or 53 ISO weeks depending on leap-year alignment.
Why ISO weeks
ISO 8601 week numbering is dominant in European business culture, in retail planning (W37, W42, W51), and in any software dealing with sprints, payroll cycles, or quarterly reports. US conventions usually number weeks starting Sunday with January 1 always in week 1, which is fine for calendars but doesn't carry over across year boundaries cleanly. ISO weeks do.
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